CN1922008A - Anti-reflection film, polarizing plate and preparation method thereof, liquid crystal display element, liquid crystal display device and image display device - Google Patents

Abstract

The present invention provides an antireflection film which is inexpensive and easy to produce and has sufficient antireflection performance, scratch resistance and stain resistance, and a polarizing plate and a liquid crystal display device using the antireflection film having such excellent performance, wherein the antireflection film includes a transparent support and a low refractive index layer having a refractive index lower than that of the transparent support, wherein the low refractive index layer is an outermost layer, and the low refractive index layer contains hollow silica particles and a compound which lowers the surface free energy of the outermost layer.

Description

Anti-reflection film, polarizing plate and preparation method thereof, liquid crystal display element, liquid crystal display device and image display device

technical field

The present invention relates to an antireflection film, a polarizer containing the antireflection film, and their preparation methods. The present invention also relates to a liquid crystal display element and an image display device such as a liquid crystal display device.

Background technique

In general, antireflection films are placed on the outermost surfaces of image display devices such as cathode ray tube display devices (CRT), plasma display panels (PDP), electroluminescent display devices (ELD) and liquid crystal display devices (LCD) . This is to prevent contrast reduction or image reflection caused by the reflection of external light on the display. Usually, it has the function of reducing the reflectivity due to the scattering of light on the convex part of the surface or the light interference of the multi-layer film.

Generally, an antireflection film is produced by forming a film of a low-refractive index layer having an appropriate thickness and a refractive index lower than that of the transparent support on a transparent support. In order to realize the low refractive index of the low refractive index layer, it is required that the material for preparing the low refractive index layer has as low a refractive index as possible. Since the antireflection film is placed on the outermost surface of the display, the antireflection film is required to have high scratch resistance. In order to achieve high scratch resistance for films with a thickness of around 100 nm, these films must have high mechanical strength and must be able to bond to the underlying layer.

In order to improve antireflection, the antireflection layer of an antireflection film formed of a multilayer film generally has a layer structure mainly composed of a high refractive index layer and a low refractive index layer. In order to achieve effective antireflection, it is stated in the literature that the difference in refractive index between the high-refractive-index layer and the low-refractive-index layer must be within a specific range (see, for example, JP-A-59-50401). For this reason, various methods have been studied. MgF ₂ and silicon dioxide are used as the low-refractive index material of the low-refractive index layer (see, for example, JP-A-2-245702); use a fluorine-containing compound (see, for example, JP-A-2003-121606); or Micropores are formed by stacking two or more kinds of inorganic particles (see, for example, JP-A-11-6902). However, virtually all of these methods are problematic because these materials are difficult to obtain and unstable, their films are not hard, not resistant to stains, and sufficiently satisfactory low-refractive-index materials have not been obtained so far.

In order to increase the mechanical strength of films to some extent to enhance their scratch resistance, methods using fluorosol-gel films are proposed in JP-A-2002-265866 and JP-A-2002-317152. However, such obvious limitations are that (1) curing the film requires long-term heating, and thus brings a large production load, and (2) the film is not resistant to saponification solution (alkali treatment liquid), and an antireflection film is formed thereon Afterwards surface saponification of the transparent plastic film substrate could not proceed. In addition, the film is not resistant to stains, which is not satisfactory. In order to simultaneously satisfy a low refractive index, good scratch resistance, and good stain resistance, a low surface free energy compound having a low refractive index, high mechanical strength, and little contamination on the surface is required. However, most of these compounds are often in a trade-off relationship, or that is, when one of these requirements is improved, the other will suffer. Therefore, it is difficult to simultaneously satisfy all requirements for lowering the refractive index and providing scratch resistance and stain resistance.

In terms of the required lowering of the refractive index, JP-A 7-287102 discloses a process of increasing the refractive index of a hard coat layer to lower the refractive index of an antireflection film. However, since the difference in refractive index between the hard coat layer and the support is large, the high refractive index hard coat layer gives color spots to the film, and the wavelength dependence of the refractive index of the film is greatly increased.

On the other hand, in JP-A-11-189621, JP-A-11-228631 and JP-A-2000-313709, a method for improving the scratch resistance of a film is proposed by adding polysiloxane Structure is added to the fluoropolymer to reduce the coefficient of friction of the film surface. This method can effectively improve the scratch resistance of the film to a certain extent, but because the film that does not have high strength and high interfacial adhesion can not be improved substantially by this method, it has sufficient scratch resistance, so Still unsatisfactory.

JP-2003-292831 discloses a low refractive index coating agent and an antireflection film. Wherein, the agent includes at least one active energy ray-curable resin containing a compound having a (meth)acryloyloxy group in a molecule, and hollow particles with an average particle diameter of 0.5-200 nm. However, there is also a problem that when such a film system is cured in an environment where the oxygen concentration is close to that in the air (oxygen concentration: about 20% by volume), the reactive groups in the film cannot sufficiently react due to curing failure, Therefore, the scratch resistance of the cured film is not good. In addition, since the low-refractive index layer in JP-2003-292831 is not processed for stain resistance, there are still problems that stains such as fingerprints or watermarks tend to adhere to the film and dirt adhered to the film is difficult to wipe off . Today, especially for applications such as televisions and monitors, good scratch resistance and good stain resistance are required.

In JP-A-7-133105 and JP-A-2001-233611, hollow silica particles are proposed as low refractive index materials. These hollow silica particles are excellent as low refractive index materials, but it has been found that when used in the low refractive index layer of an antireflection film, these hollow silica particles have poor adhesion and they make the outermost The commercial value of the layered films decreases, so their use must be limited.

JP-A-7-333404 describes an antiglare antireflection film having good gas barrier properties, antiglare and antireflection properties. However, since it requires an oxidized polysiloxane film to be formed in a CVD mode, its producibility is low compared to a wet-coated film.

The current trend in this field is that image display devices (such as LCD, PDP, CRT) have larger panels, especially toward the development of liquid crystal display devices with anti-glare and anti-reflection films installed therein. In order to protect such an expensive large-panel image display device, it is necessary to further improve the anti-glare film and the protective film of the anti-reflection film of the image display device. Specifically, it is required that the film has better visibility (neither glare nor reflection of external light in the displayed image, high image definition and transparency), and the display panel is not stained by fingerprints or dust adhered thereon. dirty, and they are highly resistant to scratches. In a liquid crystal display device (LCD), a polarizer is an essential optical material. The polarizer generally includes a polarizing sheet protected by two protective films. In order to reduce the number of constituent elements of a liquid crystal display device and reduce its cost to increase its manufacturability, it is necessary to make the protective film of the polarizer have an anti-reflection function, so that the obtained polarizer has better weather resistance, physical protection and anti-reflection. reflective. This achieves, inter alia, an increase in productivity, a reduction in costs and a reduction in the thickness of the device.

As a material of the polarizing sheet, polyvinyl alcohol (referred to as PVA hereinafter in this specification) is mainly used. Briefly, the PVA film is then uniaxially stretched, colored with iodine and a dichroic dye, or first dyed and then stretched so that it is crosslinked with a curable compound to form a polarizing sheet. Generally, the polarizer is stretched (stretched in the axial direction) in the machine direction (axial direction) of the elongated film so that the absorption axis of the polarizer is approximately parallel to the axial direction.

The protective film is an optically transparent film with small birefringence, which mainly uses cellulose triacetate. Heretofore, the protective film is adhered to the polarizing sheet in such a way that the slow axis of the protective film can be perpendicular to the transmission axis of the polarizing sheet (or that is, so that the slow axis of the protective film can be parallel to the absorption axis of the polarizing sheet). The anti-reflection treatment is achieved by using an anti-reflection film, which is a multi-layer product formed of multi-layer films of different materials with different refractive indices, and the anti-reflection film is designed to reflect in a certain range of visible light . However, in the antireflection film, the thickness of the constituent layers of the multilayer product is constant in each layer, and therefore, in principle, the antireflection film cannot fully perform its antireflection function in the entire region of visible light.

Therefore, in general, an antireflection film is designed such that its antireflection to high-visibility light of about 550 nm is enhanced and its antireflection can cover as wide a wavelength range as possible. Because the purpose of designing the film is different, the anti-reflection effect of the film is currently insufficient in a range other than a specific wavelength range, and the reflectance of the film in a part of the short-wavelength region of visible light and a part of the long-wavelength region of visible light is higher than that in the visible light region. The other wavelength regions are larger. As a result, there is a problem that the reflected light takes on a certain color tone and degrades the display quality of the image display device.

Contrary to this, various studies have been conducted on integrating a polarizing plate and an antireflection film to form an integrated adhesion product to increase the quality of displayed images. Specifically, there is disclosed a polarizer containing an antireflection film, which has a maximum reflectance of 3.5% in the range of 380-700 nm (see, for example, JP-A-2003-270441).

In reflective or transflective liquid crystal display devices, the back light used generally has bright line peaks at three wavelengths of 440 nm, 550 nm and 610 nm. Therefore, it is important to make the light transmittance the same at these three wavelengths in terms of improving the color reproducibility of the device. A polarizer containing an antireflective film is proposed, in which the parallel light transmittance and cross light transmittance at wavelengths of 440nm, 550nm and 610nm are specified (JP-A-2002-22952 and JP-A-2003- 344656).

On the other hand, in order to improve the display quality of an image display device, various optical layers are employed on the outermost side of a liquid crystal panel in addition to a polarizing plate. For example, a retardation plate (including a λ plate such as a 1/2 wavelength plate and a 1/4 wavelength plate), an optical compensation film, and a brightness improvement film are used. Specifically, an elliptical polarizing plate or a circular polarizing plate constituted by superimposing a retardation plate on a polarizing plate including a polarizing sheet and a protective layer; a polarizing plate; and a polarizing plate constituted by laminating a brightness improving film on a polarizing plate including a polarizing sheet and a protective layer.

A polarizing plate constituted by superimposing a brightness improving film on a polarizing plate including a polarizing sheet and a protective layer is generally used on the back side (low end) of a liquid crystal cell to play a role in increasing the brightness of an image display panel of an LCD (see, for example, "2003's Views and Strategies in High-Function Film Market", p.91(2003), by Yano Keizai Kenkyu-jo).

On the other hand, an anti-glare and/or reflection-reducing treatment film has been proposed for a visible end protective film of a polarizing plate mounted on the visible end (upper end) of a liquid crystal cell (see, for example, JP-A-2003- 149634).

Contents of the invention

As described above, there has been no proposed antireflection film which satisfies all the requirements of good antireflection performance, good scratch resistance and good stain resistance and also satisfies high producibility.

Accordingly, an object of the present invention is to provide an antireflection film which satisfies all the requirements of good antireflection performance, good scratch resistance and good stain resistance, and also satisfies high producibility, and can Simple and cost-effective production.

Another object of the present invention is to provide a polarizing plate equipped with the antireflection film having the above properties, and to provide a liquid crystal display device equipped with the polarizing plate.

Still another object of the present invention is to provide a liquid crystal display device comprising the antireflection film having the above excellent properties.

Still another object of the present invention is to provide an antireflection film which functions as a protective film for a display device, and which is advantageous in that it prevents glare and external light reflection on displayed images, has high scratch resistance, There is less dust sticking to it, and there is no bonding failure.

Still another object of the present invention is to provide an image display device which is advantageous in that there is no glare and external light reflection on the displayed image, and the device has good scratch resistance and no adhesion failure.

LCDs are widely used as flat panel displays, which are indispensable in the current high-level information and communication era, due to their advantages of thinness, light weight, and power saving. In particular, it is remarkable for the development of large panels or mobile monitors or televisions capable of expressing high-definition color images. High-definition color image display needs to further neutralize the tone of the displayed image. These large-scale display images also require uniformity across the panel. Specifically, in liquid crystal monitors of 15 inches or larger, it is desired to solve the problem of light leakage from around the monitor (frame breakage) caused by the shrinkage of the polarizing sheet over time.

On the other hand, it is more desirable to reduce the thickness of the polarizing plate from the viewpoint of reducing the weight of the polarizing plate element and reducing its cost. However, it has been found that when the polarizing sheet is thinned, light leakage on the short and long wavelength ends of the visible light increases under crossed Nicols, and thus the hue of the film shifts from neutral gray.

Accordingly, an object of the present invention is to provide a polarizing plate whose in-plane color tone is uniform and neutral, has good durability and has no reflection of external light thereon.

Another object of the present invention is to provide a polarizing plate that prevents light leakage at the short-wave end and long-wave end of visible light under crossed Nicols even if the polarizing sheet on it is very thin, and can have a good color tone, have a good Durability and no external light reflections on it.

Still another object of the present invention is to provide a polarizing plate having a polarizing sheet formed from a diagonally stretched polymer film, wherein the film is produced according to a diagonally stretching method and is effectively raised in a die-cutting step. Polarizer yield. The polarizer has good quality and low cost.

Still another object of the present invention is to provide an image display device having good durability and high image quality, comprising a polarizing plate provided with an antireflection film formed at one end of the polarizing plate thereof.

Liquid crystal display devices are required to have a wide viewing angle and high-speed response, and are also required to have the ability to display bright and high-definition full-color images. Specifically, in large-panel display devices of 20 inches or more, bright and clear images without uneven brightness (or luminosity) are urgently required. Furthermore, it is also desired to increase the durability and reduce the cost of polarizing plates used in these display devices.

Specifically, there is an urgent need to provide a liquid crystal display element having good optical properties and having good durability, which can be used in the above-mentioned various liquid crystal display devices.

On the other hand, with the development of the above large-sized or mobile display panels, thin and light-weight liquid crystal display devices are further required.

Conventional liquid crystal display devices cannot satisfy all of these requirements currently required, and thus it is necessary to develop a liquid crystal display device that satisfies all of these requirements.

Therefore, an object of the present invention is to provide a liquid crystal display element on which there is no reflection of external light and no glare even if assembled in a large-sized liquid crystal display device, can display images brightly and clearly, and has good durability .

Another object of the present invention is to provide a liquid crystal display element which has good durability and is thin and lightweight.

Still another object of the present invention is to provide a kind of liquid crystal display device, and it has the polarizing plate of the brightness improving film that is formed at one end of its polarizing plate, and the polarizing plate of the antireflection film that is formed at one end of its polarizing plate, and has good Durability and good display quality.

According to the present invention, there is provided an antireflective film, a polarizing plate, a method for producing the same, a liquid crystal display device element, an image display device, and a liquid crystal display device (A-1 to E-12 below) having the following constitutions, and The above-mentioned purpose is thus achieved.

A-1. (first embodiment) a kind of antireflection film, it comprises:

a transparent support; and

A low-refractive-index layer having a refractive index lower than that of a transparent support, wherein the low-refractive-index layer is the outermost layer of an antireflection film, and the low-refractive-index layer comprises: hollow silica particles and lowering the antireflection film The surface free energy of the compound.

A-2. The antireflection film of A-1 above, wherein the compound is at least one compound selected from the group consisting of silicone compounds, fluorine-containing compounds and fluoroalkylpolysiloxane compounds.

A-3. The antireflection film of the above A-2, wherein the compound is a polysiloxane compound.

A-4. The antireflection film of any of A-1 to A-3 above, wherein the low-refractive index layer includes a binder, and the compound includes a group reactive with the binder.

A-5. The antireflection film of any of A-1 to A-4 above, wherein the compound includes a (meth)acryloyl group.

A-6. (second embodiment) an antireflection film, comprising:

a transparent support; and

A low-refractive-index layer having a refractive index lower than that of a transparent support, wherein the low-refractive-index layer is the outermost layer of an antireflection film, and the low-refractive-index layer comprises: hollow silica particles and Surface free energy for binders.

A-7. The antireflection film of any item of A-1 to A-6 above, wherein at least one of the polysiloxane and the fluoroalkyl group is segregated on the outer surface of the low-refractive index layer, so that the photoelectron spectrum of the outer surface is The spectral intensity in is at least 5 times greater than Si/C or F/C than Si/C or F/C at a depth from the outer surface of 80% of the thickness of the low index layer.

A-8. The antireflection film of A-6 or A-7 above, wherein the binder includes at least one of polysiloxane and fluorine.

A-9. The antireflection film of any of A-6 to A-8 above, wherein the binder is a fluorine-containing polymer.

A-10. The antireflection film of any of A-6 to A-9 above, wherein the binder is a compound having a (meth)acryloyl group.

A-11. The antireflection film of any of A-6 to A-10 above, wherein the binder is a compound represented by formula (1):

Wherein L represents a linking group with 1-10 carbon atoms; X represents a hydrogen atom or a methyl group; A represents a repeating unit derived from a vinyl monomer; x, y and z each represent the mol% of each repeating unit, and 30≤x≤60, 5≤y≤70 and 0≤z≤65 are satisfied.

A-12. The antireflection film of any of items A-1 to A-11 above, wherein the surface free energy is at most 25 mN/m.

A-13. The antireflection film according to any of A-1 to A-12 above, which comprises a layer containing at least one of a hydrolyzate of an organosilane and a partial condensate of an organosilane, wherein the hydrolyzate and the partial condensate The compound is prepared in the presence of at least one of an acid catalyst and a metal chelate, and the organosilane is represented by formula (A):

(R ¹⁰ ) _m Si(X) _4-m

wherein R ¹⁰ represents a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; X represents a hydroxyl group or a hydrolyzable group; and m represents an integer of 1-3.

A-16. A polarizing plate comprising the antireflection film of any of the above items A-1 to A-13.

A-17. A liquid crystal display device comprising the antireflection film of any of the items A-1 to A-13 above, or the polarizing plate of A-16 above.

The antireflection films of the first and second embodiments of the present invention are simple and inexpensive to produce, and have good antireflection performance, scratch resistance and stain resistance.

Furthermore, the present invention provides a polarizing plate having the above-mentioned antireflection film of the present invention. In the liquid crystal display device of the present invention having the antireflection film or the polarizing plate, since the antireflection film is installed on the outermost surface of the panel of the liquid crystal display device, it has good visibility and good scratch resistance and durability. Stain resistance.

B-1. (the third embodiment) an antireflection film, comprising:

a transparent support; and

a low-refractive-index layer having a refractive index lower than that of the transparent support,

in

The low refractive index layer has a refractive index of 1.30-1.55,

The low refractive index layer is formed by: coating a curable composition on the transparent support; drying the curable composition; passing ionizing radiation and applying at least one of heat cures the curable composition, and

The curable composition includes: (A) a curable substance including crosslinking or polymerizing functional groups; (B) hollow inorganic particles, the average particle diameter of which is 30%-150% of the thickness of the low refractive index layer, and the hollow inorganic particles having a refractive index of 1.17 to 1.40; (C) at least one of a first polymerization initiator capable of generating free radicals by ionizing radiation and a second polymerization initiator capable of generating free radicals by application of heat; and (D) capable of dissolving Or a solvent for dispersing components (A)-(C).

B-2. The antireflection film of B-1 above, wherein the low refractive index layer further comprises at least one selected from the group consisting of the following compounds: polysiloxane compounds, fluorine-containing compounds, and fluoroalkyl polysilicon Oxygen compounds.

B-3. The antireflection film of B-1 or B-2 above, wherein the curable substance is a polyfunctional (meth)acrylate monomer.

B-4. The antireflection film of any of the above B-1 to B-3, wherein said curable composition mainly contains a curable substance, and the curable substance is a fluoropolymer,

Wherein the fluoropolymer comprises: 35-85% by weight of fluorine atoms; and cross-linking or polymerizing functional groups, and

The fluoropolymer is a copolymer, wherein the copolymer comprises: a first polymerizable unit of a fluorine-containing vinyl monomer; and a second polymerizable unit having a side branch comprising (meth)acryloyl and glycidol The functional group of one of the groups, and the copolymer has a main chain composed of carbon atoms.

B-5. The antireflective film of any of the above B-1 to B-4, wherein the curable composition further comprises at least one of an organosilane compound, a hydrolyzate of an organosilane compound, and a partial condensate of an organosilane compound Kind, the organosilane compound is represented by formula (A1):

(R ¹⁰¹ ) _m Si(X) _4-m

wherein R ¹⁰¹ represents an alkyl group; X represents a hydroxyl group or a hydrolyzable group; and m represents an integer of 1-3.

B-6. A polarizer, comprising:

polarizing sheets; and

A transparent protective film on one side of the polarizing sheet, the transparent protective film comprising the antireflection film of any of the above items B-1 to B-5.

B-7. The polarizing plate of B-6 above, having said polarizing sheet in turn; said transparent protective film on the other side of said polarizing sheet; and said optical compensation film,

in

The optically anisotropic layer includes a compound having a discoidal structure,

The disk-shaped surface of the disk-shaped structure is inclined relative to the film surface of the transparent protective film, and

The angle between the disc surface and the film surface varies in the depth direction of the optically anisotropic layer.

B-8. A liquid crystal display device comprising the polarizing plate of the above B-6 or B-7.

B-9. a preparation method of antireflective film, it comprises:

applying the curable composition to a transparent support;

drying the curable composition; and

Curing the curable composition by at least one of ionizing radiation and applying heat in an atmosphere having an oxygen concentration of not higher than 15% by volume, thereby forming a low-refractive index layer having a refractive index of 1.30-1.55 on a transparent support ,

in

The curable composition includes: (A) a curable substance including crosslinking or polymerizing functional groups; (B) hollow inorganic particles, the average particle size of which is 30%-150% of the thickness of the low refractive index layer, and the hollow inorganic particles have a refractive index of 1.17-1.40; (C) at least one of a first polymerization initiator capable of generating free radicals by ionizing radiation and a second polymerization initiator capable of generating free radicals by application of heat; and (D) capable of dissolving or Solvent for dispersing components (A)-(C).

The antireflection film of the third embodiment of the present invention has good antireflection performance as well as good scratch resistance and good manufacturability. Therefore, display devices directly having the antireflection film of the present invention or containing a polarizing plate equipped with the film, such as liquid crystal display devices, have good scratch resistance and excellent visibility because they have no external light reflection or background objects Trouble with reflection.

C-1. (the fourth embodiment) a kind of antireflection film, it comprises:

a support comprising a cellulose acylate film having a thickness of 30 to 120 μm;

An antireflection layer comprising in turn: at least one of a light-diffusing layer and a high-refractive-index layer, the high-refractive-index layer having a higher refractive index than the support; and having a higher refractive index than the support A low-refractive-index layer with a low refractive index,

in

The cellulose acylate film is a long film with a length of 100 to 5,000 m and a width of at least 0.7 m; the cellulose acylate film has a thickness fluctuation range of -3 to 3%; and the cellulose acylate film is within the width of the cellulose acylate film direction has a curl of -7-+7/m, and

The low refractive index layer includes hollow silica particles with a refractive index of 1.17-1.40.

C-2. The antireflection film of C-1 above, wherein the cellulose acylate film satisfies the formulas (I) and (II):

(I) 2.3≤SA'+SB'≤3.0,

(II) 0≤SA'≤3.0

wherein SA' refers to the degree of substitution of an acetyl group that replaces a hydrogen atom of a hydroxyl group in cellulose; and SB' refers to the degree of substitution of an acyl group having 3 to 22 carbon atoms that replaces a hydrogen atom of a hydroxyl group in cellulose atom.

C-3. The antireflection film of C-1 or C-2 above, wherein the cellulose acylate film comprises, as a plasticizer, an aliphatic polyhydric alcohol and a polyhydric alcohol ester of a monocarboxylic acid, and

The cellulose acylate film has a moisture permeability of 20-260 g/m ² for 24 hours under the conditions of 25° C. and 90% RH.

C-4. The antireflection film of any of C-1 to C-3 above, wherein the monocarboxylic acid in the polyol ester includes at least one of an aromatic ring and an alicyclic ring.

C-5. The antireflection film of any of C-1 to C-4 above, wherein the cellulose acylate film has a bleed-out degree of 0 to 2.0%.

C-6. The antireflection film of C-1 to C-5 above, wherein the cellulose acylate film comprises an ultraviolet absorbing monomer having a molar extinction coefficient of at least 4,000 at 380 nm and an ethylenically unsaturated monomer An ultraviolet absorbing copolymer, and the ultraviolet absorbing copolymer has a weight average molecular weight of 2,000-20,000.

C-7. The antireflective film of any item of C-1 to C-6 above, wherein the cellulose acylate film has a surface with the following surface roughness (or unevenness) measured according to the JIS B0601-1994 method: The arithmetic average roughness (Ra) is 0.0005-0.1 μm; the ten-point average roughness (Rz) is 0.001-0.3 μm; and the average distance (Sm) of surface roughness is 2 μm at most, and

The number of optical defects each having a visible size of at least 100 μm on the surface is at most 1/m ² .

C-8. The antireflection film of any item from C-1 to C-7 above, wherein the reflected light from the antireflection film is in the color space CE1976L ^* a ^* b ^{* L * ,} a ^* and b ^* values The maximum variation within each plane is 20%,

Wherein the reflected light is regular reflected light of incident light with an incident angle of 5 degrees, the incident light has a wavelength of 380nm-780nm, and the incident light is light from CIE standard light source D65.

C-9. The antireflection film of any of the above C-1 to C-8, wherein the change in the average reflectance in the wavelength range of 380nm-680nm before and after the weathering test is 0.4% at most, and

The hue change ΔE of reflected light on the L ^* a ^* b chromaticity diagram is 15 at maximum.

C-10. The antireflection film of any of the above C-1 to C-9, which comprises a transparent layer containing a conductive material between the cellulose acylate film and the light-diffusing layer or the cellulose acylate film and the high refractive index layer antistatic layer,

Wherein the transparent antistatic layer has a maximum surface resistivity of 2×10 ¹² Ω/□; a maximum haze of 20%; and a light transmittance of at least 50% at a wavelength of 550 nm.

C-11. The antireflection film of any of the items C-1 to C-10 above, wherein said transparent antistatic layer is a curable resin layer containing conductive inorganic fine particles having an average particle diameter of 3-100 nm. primary particle size, and

The surface roughness of the surface of the transparent antistatic layer was: arithmetic mean roughness (Ra) of at most 0.03 μm; ten-point average roughness (Rz) of at most 0.06 μm; and maximum height (Ry) of at most 0.09 μm.

C-12. The antireflection film of any of the above C-1 to C-10, wherein the low refractive index layer further comprises a composition comprising a hydrolyzate of an organosilane and a partial condensate of an organosilane at least one, and the organosilane is represented by formula (A2):

R _m Si(X) _n

Wherein X represents -OH, a halogen atom, -OR ¹⁰² or -OCOR ¹⁰² ; R and R ¹⁰² each represent a substituted or unsubstituted alkyl group with 1-10 carbon atoms; m+n=4, and m and n are each Represents an integer of 0 or greater.

C-13. The antireflection film of any of C-1 to C-12 above, wherein said transparent antireflection layer has an outermost surface having a surface free energy of 15-26 mN/m and a kinetic friction coefficient of 0.05-0.20.

C-14. The antireflection film of any of C-1 to C-13 above, wherein the low refractive index layer further includes a fluorine-containing compound having a curable reactive group.

C-15. A polarizer comprising:

polarizing sheets; and

A transparent protective film on one side of the polarizing sheet, the transparent protective film comprising the antireflection film of any of items C-1 to C-14 above.

C-16. A polarizer, comprising:

Polarizing sheet;

A first transparent protective film on one side of the polarizer, the transparent protective film comprising the antireflection film of any item from C-1 to C-14 above; and

A second transparent protective film on the other side of the polarizer, the second transparent protective film is an optical compensation film with optical anisotropy.

C-17. An image display device comprising the antireflection film of any of C-1 to C-14 above or the polarizing plate of C-15 or C-16 above.

The cellulose acylate film used as a support in the antireflection film of the fourth embodiment of the present invention is a long calendered film having a length of 100 to 5,000 m, a width of at least 0.7 m, and a thickness fluctuation of ±3%. range, and its curling in the width direction is -7/m to +7/m. On the side coated with the antireflection layer, the surface roughness of the film preferably has a specific roughness distribution measured according to the method of JIS B0601-1994.

Therefore, even if the film has a long-calendered shape, a uniform antireflection layer without coating unevenness can be formed, and furthermore, the layer can be adhered well to a support. The antireflection film thus formed is prevented from having optical defects and can delay fluctuations in thickness thereof, with the result that unevenness in color tone of reflected light on the reflection film can be reduced.

The cellulose acylate film preferably used as a support for the antireflection film of the fourth embodiment of the present invention includes cellulose acylate having a specific composition ratio as its main component, and is preferably formed according to a solution casting film-forming method. In addition, the film contains a plasticizer capable of improving the physical properties of the film (curl resistance, dimensional stability, scratch strength, moisture resistance), the plasticizer is uniformly dispersed without segregation in the film, and controls the film's Moisture permeability falls within the scope defined in the present invention. As a result, the film maintains good transparency and its physical properties are improved as described above.

The exudation of the plasticizer is small, and this can be beneficial to improve the inner layer adhesion of the film. Bleeding out means that when the film is in a high-temperature, high-humidity environment, additives such as plasticizers contained therein seep out of the film and evaporate, whereby the weight of the film decreases.

Also, the cellulose acylate film used in the present invention contains an ultraviolet absorbing copolymer of an ultraviolet absorbing monomer and an ethylenically unsaturated monomer, and has a specific molar extinction coefficient. Therefore, the ultraviolet absorber was hardly deposited on the outside of the film, and the image clarity and adhesiveness were good.

The anti-reflection film of the fourth embodiment of the present invention is characterized in that: when the incident light from the CIE standard light source D65 with a wavelength range of 380nm-780nm is irradiated on the anti-reflection film with an angle of incidence of 5 degrees, its regular reflection light is at The respective in-plane variations of L ^* , a ^*, and b ^* values in the color space CE1976L ^* a ^* b ^* are 20% maximum, and when measured according to the JIS K5600-7-7:1999 method, the film before and after the weathering test , the reflected light hue change ΔE on the L ^* a ^* b chromaticity diagram is 15 at most. Therefore, the film satisfies both requirements of low reflection and reduced reflection color. As for indoors with fluorescent lamps, when bright external light is reflected on the film, the film's color tone is neutral, and the film maintains good display image quality.

By optimizing the balance between the refractive index of the low refractive index layer and the refractive index of the translucent resin to form an anti-glare hard coat of the high refractive index layer of the film, it is possible to obtain a neutrally reflected light thereon Anti-reflection film with low refractive index.

Preferably, the antireflection film of the fourth embodiment of the present invention further has a transparent antistatic layer between its support and the light-diffusing layer. Specifically, the layer can be formed by applying a curable composition containing conductive inorganic fine particles on a support and then curing it on the support. In this way, films with long calendered forms can be formed with high productivity. The antistatic layer thus formed in the film has a specific roughened surface in which there are no optical defects, and the coating formed thereon can have a uniform surface and have good adhesion to the underlying layer. We have discovered the advantages of the present invention.

Also, the surface free energy of the outermost surface of the antireflection layer (the outermost surface of the antireflection film) is preferably at most 26 mN/m, and its kinetic friction coefficient is preferably at most 0.25. More preferably, its surface free energy is 15-25.8 mN/m and its kinetic coefficient of friction is 0.05-0.25; even more preferably its surface free energy is 15-22 mN/m and its kinetic coefficient of friction is 0.05-0.15. Within this range, the stain resistance of an antireflection film also used as a protective film is good. Surface free energy control is described in detail in the <Low Refractive Index Layer> section.

The low-refractive-index layer of the antireflection film of the fourth embodiment of the present invention preferably contains a composition comprising any one of hydrolyzate or partial condensate of organosilane. With it, the adhesion of the layer will be further improved and the scratch resistance of the surface will be further improved.

The antireflection film of the fourth embodiment of the present invention can be used as a protective film of a display device, and its advantages are that the displayed image is not dazzled and there is no external light reflection on it, the images are clear and their visibility is good, and the reflected light on it The color tone of is almost neutral and gives a good image on film. In addition, the film has good adhesion, good durability and weather resistance. Also, the productivity of the film is good, and the film can be produced at low cost.

The polarizing plate of the present invention contains the above-mentioned antireflection film of the present invention, and has good quality and durability.

The image display device of the present invention contains the above-mentioned antireflection film or polarizing plate of the present invention, and has good durability and good image quality.

D-1. A polarizer comprising:

polarizing sheets; and

transparent protective film on each side of the polarizing sheet,

in

The transparent protective film on one side of the polarizing sheet has a multilayer antireflection film,

The multilayer antireflection film comprises a high-refractive-index layer whose refractive index is higher than that of the transparent protective film; and a low-refractive-index layer whose refractive index is lower than the refractive index of the transparent protective film,

The high-refractive-index layer and the low-refractive-index layer are formed by sequentially applying their respective coating liquids,

The low refractive index layer includes hollow inorganic particles having a refractive index of 1.17-1.37 and an average particle diameter of 30%-100% of the thickness of the low refractive index layer.

D-2. The polarizing plate of D-1 above, which has a first light transmittance of 0.001%-0.3% at 700 nm under crossed Nicols conditions, and has a first light transmittance at 410 nm under crossed Nicols conditions 0.001%-0.3% second light transmittance.

D-3. The polarizer of D-1 or D-2 above, which has:

When the incident light obtained from ^the CIE standard light source D65 in the wavelength ^range of 380nm-780nm is irradiated at an incident angle ^{of 5 degrees, the first regular reflection light on the polarizer has a* and} b ^* values, where the a ^* and b ^* values satisfy 0≤a ^* ≤7 and -10≤b ^* ≤0; and

Another a ^* and b ^* value in the color space of the second regular reflection light of the incident light with an incident angle of 5-45°, wherein the a ^* and b ^* values satisfy a ^* ≥0 and b ^* ≤0.

D-4. The polarizing plate of any of the items D-1 to D-3 above, wherein the reflected light reflected from the polarizing plate is on the respective planes of L ^* , a ^* and b ^* values in the color space CE1976L ^* a ^* b ^* within a variation of not more than 20%,

Wherein the reflected light is regular reflected light of incident light with an incident angle of 5 degrees, the incident light has a wavelength of 380nm-780nm, and the incident light is light from CIE standard light source D65.

D-5. The polarizing plate according to any item of D-1 to D-4 above, wherein the high refractive index layer includes two high refractive index layers with different refractive indices, and the antireflection film has at least 3 layers, at least 3 The layer satisfies the numerical formula (IV-2)-(IV-4):

(IV-2)(m ₁ λ/4)×0.60<n ₁ d ₁ <(m ₁ λ/4)×0.80

(IV-3)(m ₂ λ/4)×1.00<n ₂ d ₂ ＜(m ₂ λ/4)×1.50

(IV-3)(m ₃ λ/4)×0.85<n ₃ d ₃ ＜(m ₃ λ/4)×1.05

Wherein m ₁ is 1; n ₁ is the refractive index of the middle refractive index layer with a lower refractive index among the two high refractive index layers; d ₁ is the thickness (nm) of the middle refractive index layer; m ₂ is 2 ; n ₂ is the refractive index of the higher refractive index layer with the higher refractive index among the two high refractive index layers; d ₂ is the thickness (nm) of the higher refractive index layer; m ₃ is 1; n ₃ is the Refractive index of the low refractive index layer; d ₃ is the thickness (nm) of the low refractive index layer; λ is the wavelength of light used for measurement.

D-6. The polarizing plate of any of D-1 to D-4 above, wherein said high refractive index layer is a light scattering layer comprising: a translucent resin; and translucent particles having an average particle diameter of 0.5-5 μm , wherein the translucent particles are dispersed in the translucent resin, and

The refractive index difference between the translucent particles and the translucent resin of the high refractive index layer is 0.02-0.5.

D-7. The polarizing plate of any of D-1 to D-6 above, wherein the transparent protective film is one having a moisture permeability of 400 g/m ² 24 hours - 2,000 g/m at 60° C. and 95% RH ² · 24-hour cellulose acylate film.

D-8. The polarizing plate of any of the above D-1 to D-7, wherein in absolute value, the light transmittance of the polarizing plate before and after standing for 500 hours in an environment of 60° C. and 90% RH and None of the polarization changes exceeded 3%.

D-9. The polarizing plate of any of the above D-1 to D-8, wherein the polarizing plate is in each direction of the absorption axis and the polarization axis before and after the polarizing plate is left to stand under a heating condition of 70° C. for 120 hours Dimensional variation is within ±0.6%.

D-10. The polarizing plate of any of D-1 to D-9 above, wherein the angle between the stretching axis of the transparent protective film and the stretching axis of the polarizing sheet is from 10° to less than 90°.

D-11. The polarizing plate of any of D-1 to D-10 above, wherein said transparent protective film on the other side of the polarizing plate has an optical compensation film comprising an optically anisotropic layer.

D-12. A method for preparing the polarizer of D-1 above, comprising:

Polymer films for polarizing sheets;

clamping each side of the polymer film; and

The polymer film is stretched by applying tension to the polymer film while moving the gripper in the axial direction of the polymer film,

in

Stretching is carried out under the condition of satisfying formula (III):

|L2-L1|＞0.4W

Where L1 represents the trajectory of the first clamp from the real clamping start point to the real clamping release point on one side of the polymer film; L2 represents the trajectory of the second clamp from the real clamping start point to the real clamping release point on the other side of the polymer film point locus; and W represents the distance between the two real clamping release points of the first clamp and the second clamp, and

The difference in moving speed between the first gripper and the second gripper is less than 1%.

D-13. The production method of the polarizing plate of D-12 above, wherein the stretching is carried out under the condition of maintaining the volatile matter content of the polymer film at least 5% by volume, and the volatile matter content is reduced while the polymer film shrinks.

D-14. A method for producing the polarizing plate of D-12 or D-13 above, which comprises sticking a transparent protective film on one side of the polarizing plate, and the protective film has an antireflection film.

D-15. An image display device comprising the polarizing plate of any one of D-1 to D-11 above, the polarizing plate being mounted on an image display of the image display device.

D-16. The image display device of D-15 above, which is a transmissive, reflective or semi-transmissive liquid crystal display device in any mode of TN, STN, IPS, VA or OCB.

According to the present invention, there is provided a polarizing plate having a uniform and neutral in-plane hue and good durability. This polarizer has no trouble with external light reflecting on it. Even if the polarizing sheet in the polarizer of the present invention is very thin, the polarizer can still effectively prevent light leakage of short-wave and long-wave visible light under crossed Nicols. Therefore, the polarizing plate has good color tone and good durability, and has no trouble of external light being reflected thereon. In the method for producing a polarizing plate of the present invention, a diagonally stretched polymer film is used for a polarizing sheet, and the yield is high in the step of punching the film into a polarizing plate. Therefore, the polarizer of the present invention has good quality and low cost. The image display device of the present invention has the polarizing plate on its image display face side, and thus has good durability and good image quality.

E-1. A liquid crystal display element, which comprises successively:

upper polarizer;

A liquid crystal cell comprising two cell substrates; and

A lower polarizer, wherein the upper polarizer and the lower polarizer each sequentially include: an upper transparent protective film, a polarizing sheet, and a lower transparent protective film, and the lower polarizer includes a brightness improving film,

in

The upper transparent protective film comprises: a transparent support and an anti-reflection film, the anti-reflection film comprises a low-refractive-index layer with a lower refractive index than the transparent support, wherein the low-refractive layer is the outermost layer of the transparent support , and the low refractive index layer includes hollow inorganic particles having a refractive index of 1.17-1.37 and an average particle diameter of 30%-100% of the thickness of the low refractive index layer.

E-2. The liquid crystal display element of E-1 above, wherein the low refractive index layer is a cured film formed by applying and curing a curable composition,

Wherein the curable composition comprises: hollow inorganic particles, a fluoropolymer including curable reactive groups, and at least one of a hydrolyzate of an organosilane and a partial condensate of an organosilane, wherein the hydrolyzate and the partial condensation The compound is prepared in the presence of at least one of an acid catalyst and a metal chelate, and the organosilane is represented by formula (A):

(R ¹⁰ ) _m Si(X) _4-m

wherein R ¹⁰ represents a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; X represents a hydroxyl group or a hydrolyzable group; and m represents an integer of 1-3.

E-3. The liquid crystal display element of E-1 or E-2 above, wherein the antireflection film comprises a film having a refractive index higher than that of the transparent support between the low refractive index layer and the transparent support High refractive index layer.

E-4. The liquid crystal display element of E-1 or E-2 above, wherein the antireflection film has a refractive index between the low refractive index layer and the transparent support that is higher than the refractive index of the transparent support Anti-glare layer.

E-5. The liquid crystal display element of any of the items E-1 to E-4 above, wherein the upper polarizing plate comprises in order from the outermost side of the upper polarizing plate: an antireflection film; a transparent support; a polarizing sheet; and another A transparent support, which is bonded and integrated as the upper polarizer.

E-6. The liquid crystal display element of any of the above items E-1 to E-5, wherein the upper polarizing plate further includes an optical compensation film on the side adjacent to the liquid crystal cell.

E-7. The liquid crystal display element of any of E-1 to E-6 above, wherein the lower polarizing plate comprises in order from the side adjacent to the liquid crystal cell: an optical compensation film; a polarizing sheet, a transparent protective film and a brightness improving film.

E-8. The liquid crystal display element of any of the items E-1 to E-7 above, wherein the transparent support is a cellulose acylate film containing cellulose acylate, octanol- A plasticizer having a water partition coefficient (log P) of 0-10 and fine particles having an average primary particle diameter of 3-100 nm, and the cellulose acylate film has a thickness of 20-120 μm:

(I) 2.3≤SA'+SB'≤3.0,

(II) 0≤SA'≤3.0

wherein SA' refers to the degree of substitution of an acetyl group used to replace a hydrogen atom of a hydroxyl group in cellulose; and SB' refers to the degree of substitution of an acyl group having 3 to 22 carbon atoms used to replace a hydrogen atom of a hydroxyl group in cellulose .

E-9. The liquid crystal display element of any item from E-1 to E-8 above, wherein the reflected light from the antireflection film is in the color space CE1976L ^* a ^* b ^{* L * ,} a ^* and b ^* values Each in-plane variation is less than 15%,

Wherein the reflected light is regular reflected light of incident light with an incident angle of 5 degrees, the incident light has a wavelength of 380nm-780nm, and the incident light is light from CIE standard light source D65.

E-10. The liquid crystal display element of any of E-1 to E-8 above, wherein the change in the average reflectance of the antireflection film in the wavelength range of 380nm-680nm before and after the weathering test is at most 0.5%, and

The hue change ΔE of the reflected light from the antireflection film was 15 at the maximum on the L ^* a ^* b chromaticity diagram.

E-11. A liquid crystal display device comprising the liquid crystal display element of any of the above items E-1 to E-10.

E-12. The liquid crystal display device of E-11 above, further comprising a backlight.

The displayed image of the liquid crystal display element of the present invention is bright and clear, and the image is not blurred and has no image unevenness and brightness unevenness.

In the liquid crystal display element of the present invention, if the antireflection film is directly laminated on the polarizing sheet, the element can be made thinner and its weight can be reduced. Therefore, using this element, the display device can be made thinner and lighter in weight, and its cost can be reduced. Since the display device includes a specific anti-reflection film, its weather resistance is good and its life can be extended.

Also, when an optical compensation film is laminated on the face of the liquid crystal cell of the element of the present invention, the viewing angle of a liquid crystal display device including the element can be widened, and this configuration is particularly effective in large panel displays. Furthermore, since the optical compensation film is directly formed on the protective film of the polarizing sheet, the element can be made thinner and its weight can be lowered. Therefore, using this element, the display device can be made thinner, and its weight and cost can be reduced.

Since the liquid crystal display device of the present invention contains the liquid crystal display element of the present invention, it provides bright and clear display images free from image blurring and image unevenness and brightness unevenness.

The antireflection film of the invention can be produced by a method with simple operation and low cost, and has good antireflection performance, scratch resistance and stain resistance. In addition, according to the present invention, there is provided a method for producing an antireflective film with excellent film thickness uniformity.

Furthermore, the present invention provides a polarizing plate comprising the above-mentioned antireflection film of the present invention. In the liquid crystal display device of the present invention including the antireflection film or polarizing plate, since the antireflection film is installed on the outermost surface of its panel, it has good visibility and good scratch resistance and stain resistance.

Description of drawings

Fig. 1 is a schematic cross-sectional view showing an example of the antireflection film of the present invention.

Fig. 2 is a schematic cross-sectional view showing the layer structure of the antireflection film of the present invention.

Fig. 3 is a schematic cross-sectional view showing the layer structure of the multilayer antireflection film of the present invention.

Fig. 4 is a schematic cross-sectional view showing a preferred embodiment of the antireflection film of the present invention.

Fig. 5 is a schematic cross-sectional view showing an example of a preferred embodiment using a high refractive index layer as an antireflection film of the present invention.

Fig. 6 is a schematic cross-sectional view showing one example of the configuration of an apparatus for continuously coating layers.

Fig. 7 is a schematic plan view showing an example of a method of obliquely stretching a polymer film.

Explanation of reference signs

1 Anti-reflection film

2 transparent base

3 conductive layer

4 hard coat

5 medium refractive index layer

6 High refractive index layer

7 Low refractive index layer

8 matt particles

9 light scattering layer

10 translucent particles

11 light diffusing layer

12 translucent resin

13 first translucent particles

14 second translucent particles

100, 200, 300, 400 film forming units

101, 201, 301, 401 Steps of applying coating liquid

102, 202, 302, 402 The step of drying the coating film (or coating solution)

103, 203, 303, 403 Step of curing coated film

(i) film adding direction

(ii) Direction of film transport to the next step

(a) Thin film addition step

(b) film stretching step

(c) Move the stretch film forward to the next step

Film engagement position and film stretching start position in gripper A1 (valid start position for right gripper)

Membrane engagement position in the B1 fixture (left)

C1 film stretching start position (effective start position for clamping on the left)

Cx Film release position and reference position of film stretching end point (effective end position of clamping on the left)

Ay The reference position of the film stretching end point (the effective end point position of the clamping on the right)

|L1-L2| Difference in travel length between left and right film grippers

W effective film width at the end of the stretching step

θ Angle between stretch direction and film advance direction

21 Membrane Centerline on Inlet Side

22 Advance to the next step to the centerline of the film

23 Trajectories of film clamps (right side)

24 Traces of film grippers (left)

25 Membrane on inlet side

26 Advance to the next film

27, 27' at the start (engagement) point of the film on the left and right

28, 28' at the release points of the left and right film clamps

Detailed ways

In this specification, when numerical data shows physical data or characteristic data, the expression "one quantity to another quantity (or from one quantity to another quantity)" refers to a quantity falling within the preceding quantity and the following quantity (including two or) range between.

<Anti-reflection film>

The basic configuration of a preferred embodiment of the antireflection film of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic cross-sectional view illustrating an example of an antireflection film according to first and second embodiments of the present invention. Here, the antireflection film 1 has a layer structure in which a transparent support 2, a conductive layer 3, a hard coat layer 4, a medium refractive index layer 5, a high refractive index layer 6, and a low refractive index layer 7 are stacked in this order. The medium refractive index layer 5 and the high refractive index layer 6 are optional layers which may or may not be present in the layer configuration, and the hard coat layer 4 may optionally contain matte particles 8 or may not contain them. Preferably, the refractive index of the low refractive index layer 7 is 1.38-1.49. When there are high-refractive-index layer 6 and medium-refractive-index layer 5 in the layer structure, their refractive index can satisfy following condition: "refractive index of low-refractive-index layer 7<refractive index of medium-refractive-index layer 5<high-refractive-index Refractive index of layer 6". Although not essential, an electrically conductive layer 3 is preferably present in the layer structure. The conductive layer 3 may not be between the transparent support 2 and the hard coat layer 4, but may be at any position in the construction of the antireflection film. The conductive layer 3 can be integrated with any layer in the layer structure, if desired.

Fig. 2 is a cross-sectional view illustrating a preferred embodiment of an antireflection film of a third embodiment of the present invention. This embodiment is a preferred example of an antiglare-antireflective film that has good scratch resistance and exhibits good antiglare properties when applied to a high definition display.

The antireflection film 1 of the embodiment of FIG. 2 includes a transparent support 2 , a light scattering layer 9 formed on the transparent support 2 , and a low refractive index layer 7 formed on the light scattering layer 9 .

The light scattering layer 9 includes a translucent resin and translucent particles 10 dispersed in the translucent resin.

In the present embodiment, the light-scattering layer 9 is used as an anti-glare and a hard coat layer. In this embodiment this is one layer, but may consist of multiple layers, for example, 2-4 layers. As in this embodiment, it can be mounted directly on a transparent support, but they can also be mounted on a transparent support via any other layer such as an antistatic layer or a moisture barrier layer.

In this embodiment, ideally, the reflected light under the C light source satisfies the conditions that the a ^* value is -2-2, the b ^* value is -3-3, and the minimum and maximum values of the refractive index are within the range of 380nm-780nm The ratio falls within the range of 0.5-0.99, since the hue of the reflected light can be neutral under such conditions. Also preferably, the b ^* value of the transmitted light under the C light source is 0-3, since the yellow tint expressed through the white color of the film can be reduced when the film is applied to a display device. Likewise preferably, a 120 μm×40 μm lattice is inserted between the planar light source and the antireflection film according to the invention, so that the standard deviation of the luminance distribution measured on the film can be at most 20. This is due to the fact that when such films of the present invention are applied to high definition panels, the glare on the panels is effectively reduced.

Fig. 3 is a cross-sectional view illustrating another preferred embodiment of the antireflection film of the third embodiment of the present invention. This embodiment is a preferred example of a clear type multilayer antireflection film whose average refractive index is reduced to 0.5% or less. Therefore, it is preferably used in televisions and monitors.

The antireflective film 1 of the present embodiment of Fig. 3 comprises transparent support body 2, the hard coat layer 4 that forms on transparent support body 2, and the middle refractive index layer 5 that all forms on hard coat layer 4, high refractive index layer 6 and low refractive index layer 7.

As for its optical properties, the antireflection film of this embodiment preferably has a specular reflectance of at most 0.5% and a light transmittance of at least 90%, so that reflection of external light thereon can be prevented and good visibility can be exhibited.

Based on FIG. 4 , which is a schematic cross-sectional view illustrating a preferred embodiment of the antireflection film of the fourth embodiment of the present invention, a preferred example of the light-diffusing layer of the present invention is described.

The antireflection film 1 includes a support 2 , a light-diffusing layer 11 formed on the support 2 , and a low-refractive-index layer 7 formed on the light-diffusing layer 11 . The light-diffusing layer 11 includes two different types of translucent particles 13 and 14 dispersed in a translucent resin 12 .

With this design, the light diffusion layer may have an irregular rough surface formed by the first translucent particles and the second translucent particles therein.

In FIG. 4, the surface is roughened due to the irregularities of the translucent particles, but the light-diffusing layer without surface roughness may be machined or polished so as to have a rough surface.

<High Refractive Index Layer>

The antireflection film of the fourth embodiment of the present invention optionally includes at least one high-refractive index layer and the above-mentioned light-diffusing layer to have better antireflection performance.

The refractive index of the high refractive index layer is 1.55-2.40. As long as the layer configuration of the antireflection film has layers whose refractive index falls within this range, it can be said that the film contains a high refractive index layer. This range of refractive index is generally used for higher and intermediate refractive index layers. However, in this specification, these layers are generally referred to as "high refractive index layers". When a film includes multiple high-refractive-index layers, it may be referred to as high-refractive-index layer-1, high-refractive-index layer-2, etc., depending on the difference in refractive index between them. When the film includes both a higher refractive index layer and a medium refractive index layer, the layer with a refractive index of 1.8-2.4 can be called a higher refractive index layer, and the layer with a refractive index of 1.55 to less than 1.8 can be called a medium refractive index layer. rate layer. However, the higher/medium index relationship between these layers is relative to each other, and the boundary index can vary by about 0.2. The refractive index can be appropriately controlled according to the types and ratios of inorganic particles and binders added.

Fig. 5 is a schematic cross-sectional view illustrating a preferred embodiment of the antireflection film of the present invention, which includes a high refractive index layer. In FIG. 5 , an antireflection film 1 includes a support 2 , a hard coat layer 4 , a high-refractive-index layer-1 ( 5 ), a high-refractive-index layer-2 ( 6 ), and a low-refractive-index layer 7 .

<Low Refractive Index Layer>

First, the low refractive index layer of the present invention will be described.

From the viewpoint of reducing the reflectance of the low-refractive layer, it is preferable that the low-refractive layer in the antireflection film of the present invention satisfies the following formula (IV-1).

(IV-1)(mλ/4)×0.7<n ₁ d ₁ <(mλ/4)×1.3

Wherein m is a positive odd number; n ₁ is the refractive index of the low refractive index layer; d ₁ is the thickness (nm) of the low refractive index layer; λ is the wavelength falling into the range of 500-550 nm. Satisfying formula (IV-1) means that there exists m (which is a positive odd number, and usually 1), which satisfies formula (IV-1) in the above-mentioned wavelength range.

The refractive index of the low refractive index layer in the antireflection film of the present invention is preferably 1.30 to 1.55 from the viewpoint of the antireflection performance and mechanical strength of the film. It is also preferred that the low refractive index layer has a lower refractive index than that of the support, more preferably 0.02-0.2 lower than that of the support.

Specifically, the refractive index of the low-refractive-index layer in the antireflection film of the first and second embodiments of the present invention is preferably 1.38-1.49, more preferably 1.38-1.44. In a third embodiment, the refractive index is preferably 1.30-1.55, more preferably 1.35-1.40. In the fourth embodiment, the refractive index is more preferably 1.31-1.48.

In the antireflection film of the present invention, the low-refractive index layer is preferably the outermost layer having scratch resistance and stain resistance.

The low refractive index layer contains inorganic particles with a hollow structure (hollow inorganic particles). Also preferably, fluorine-containing or polysiloxane-containing compounds (compounds that lower the surface free energy of the layer) and binders (binders that can lower the surface free energy of the layer) can be added to the layer thereby reducing the antireflection The surface free energy of the film.

<Inorganic particles>

The refractive index of the inorganic particles located in the low refractive index layer of the present invention may be 1.17-1.40, preferably 1.17-1.35, more preferably 1.17-1.30. The refractive index mentioned here for the particles refers to the refractive index of the entire particle. Therefore, in hollow inorganic particles, the refractive index is not only for its inorganic outer shell part. In this case, when the radius of the cavity in the particle is represented by "a" and the radius of the shell of the particle is represented by "b", the porosity "x" of the particle represented by the following formula (V) is preferably 10 to 60% , more preferably 20-60%, most preferably 30-60%.

(V)x＝(4πa ³ /3)/(4πb ³ /3)×100

When the refractive index of the hollow inorganic particles is further lowered and the porosity thereof is further increased, the thickness of the shell becomes thinner and the mechanical strength of the particles decreases. Therefore, low-refractive-index particles having a refractive index lower than 1.17 are not feasible from the standpoint of their scratch resistance.

The refractive index of the inorganic particles was measured with Abbe's refractometer (manufactured by Atago).

One example of inorganic fine particles is hollow silica particles. Hollow silica is most preferred from the viewpoints of refractive index, hardness and cost. The inorganic particles may be crystalline or amorphous, and may be monodisperse particles or aggregated particles as long as they satisfy a predetermined particle diameter. As to their morphology, the particles are most preferably spherical, but may be amorphous without any problem.

The production method of hollow silica is described, for example, in JP-A-2001-233611 and JP-A-2002-79616.

From the viewpoint of reducing the refractive index of the low-refractive index layer, improving the scratch resistance of the layer, improving the black appearance of the layer due to the formation of protruding parts of the particles, and preventing the increase of the total reflection of the layer, the coating of inorganic particles The amount is preferably 1 mg/m ² -100 mg/m ² , more preferably 5 mg/m ² -80 mg/m ² , even more preferably 10 mg/m ² -60 mg/m ² . The average particle diameter of the inorganic particles is preferably 20% to 150%, more preferably 30% to 100%, even more preferably 40% to 70%, of the thickness of the low refractive index layer. Therefore, when the thickness of the low refractive index layer is 100 nm, the particle size of the inorganic particles is preferably 30 nm to 150 nm, more preferably 30 nm to 100 nm, even more preferably 40 nm to 70 nm.

When the particle size thereof falls within the above range, the inorganic particles can effectively lower the refractive index of the low-refractive index layer, prevent the formation of protrusions on the surface of the layer, improve the black appearance of the layer and reduce the total reflection on the layer .

Inorganic particles can be crystalline or amorphous. Preference is given to monodisperse particles. As for the shape, a spherical shape is most preferable, but it may be amorphous without any problem.

The average particle diameter of the inorganic particles can be determined on an electron micrograph of the particles.

In the present invention, non-hollow silica or other arbitrary inorganic particles may be used together with the hollow inorganic particles. The other inorganic particles other than silicon dioxide are preferably particles of low refractive index compounds such as fluorine particles (magnesium fluoride, calcium fluoride, barium fluoride). The particle size of the non-hollow inorganic particles is preferably 30nm-150nm, more preferably 35nm-80nm, most preferably 40nm-60nm.

Preferably, at least one inorganic particle having an average particle diameter less than 25% of the thickness of the low-refractive index layer (referred to as "small-diameter inorganic particles") is combined with inorganic particles having the above-mentioned particle diameter (referred to as "large-grained particles"). diameter inorganic particles") mixing.

Since the small-diameter inorganic particles can exist in the spaces between the large-diameter inorganic particles, they can be used as holders for the large-diameter inorganic particles.

The average particle diameter of the small-diameter inorganic particles is preferably 1 nm to 20 nm, more preferably 5 nm to 15 nm, even more preferably 10 nm to 15 nm. Such inorganic particles are preferably used from the viewpoints of the cost of materials and the effect of the particles as anchors.

(Hollow) inorganic particles and other inorganic particles can be subjected to physical surface treatment such as plasma discharge treatment or corona discharge treatment, or chemical surface treatment with surfactants or coupling agents to ensure that they remain in the dispersion or coating liquid Dispersion stability and improve their affinity and binding ability with adhesive components. More preferably, treatment with a coupling agent is used. The coupling agent is preferably an alkoxy metal compound (for example, a titanium coupling agent, a silane coupling agent). In particular, treatment with a silane coupling agent having an acryloyl or methacryloyl group is particularly effective.

Before preparing the coating solution for the low refractive index layer, the coupling agent is used as a surface treatment agent for the inorganic filler in the layer for surface treatment, but it is preferred to add it as an additive to the coating of the layer while preparing the coating solution. liquid and thus added to the layer.

In order to reduce the load on the surface treatment, it is preferred to disperse (hollow) inorganic particles and other inorganic particles in the medium prior to surface treatment.

<Surface Free Energy>

With reference to SKOwens, J.Appl.Polym.Sci., 13,1741 (1969), the surface free energy (γs ^v of the present invention: unit, mN/m) of the antireflection film of the present invention is given as value γs ^v (=γs ^d +γs ^h ) The calculated surface tension definition of the anti-reflection film, or that is, according to the following simultaneous equations (1) and (2) from the pure water H ₂ O and diiodomethane CH ₂ I tested on the anti-reflection film The sum of γs ^d + γs ^h obtained for contact angles θ _H2O and θ _CH2I2 of ₂ . When γs ^v is small and the surface free energy is low, the film has high repellency and thus good stain resistance. Preferably, the surface free energy of the antireflection film is at most 26 mN/m, more preferably at most 25 mN/m, even more preferably at most 20 mN/m.

(1)1+cosθ _H2O ＝2√γs ^d (√γ _H2O ^d /√γ _H2O ^v )+2√γs ^h (√γ _H2O ^h /√γ _H2O ^v )

(2)1+cosθ _CH2I2 ＝2√γs ^d (√γ _CH2I2 ^d /√γ _CH2I2 ^v )+2√γs ^h (√γ _CH2I2 ^h /√γ _CH2I2 ^v )*γ _H2O ^d ＝21.8，γ _H2O ^h ＝ 51.0, γ _H2O ^v = 72.8, γ _CH2I2 ^d = 49.5, γ _CH2I2 ^h = 1.3, γ _CH2I2 ^v = 50.8. The antireflective film was conditioned for at least 1 hour at 25°C and 60% RH. The contact angle was measured on the antireflection film under the same conditions as the pretreatment.

The compound for reducing surface free energy (surface free energy reducing compound) and the binder capable of reducing surface free energy (surface free energy reducing binder) used in the present invention may be arbitrary, and there is no difference in structure and composition thereof. limit, as long as it is effective to significantly reduce the surface free energy of the antireflective film defined above when it is applied to the film. In general, the decrease in surface free energy is not linear with respect to the amount of compound applied to the film, it saturates as the amount increases. For example, the surface free energy reduction point is plotted against the amount of the curing matrix formed by the binder such as DPHA, and in the surface free energy reduction distribution curve thus prepared, the surface free energy reduction point is plotted against the amount of the compound added to the surface free energy reduction saturation point The free energy reduction is preferably at least 10 mN/m, more preferably at least 20 mN/m, even more preferably at least 25 mN/m, most preferably at least 30 mN/m.

<Surface Free Energy Reducing Compound>

The surface free energy lowering compound may be any known polysiloxane compound, fluorine-containing compound or fluoroalkyl polysiloxane compound. Preferably, the amount of the compound added to the low refractive index layer is 0.01-20% by weight, more preferably 0.05-10% by weight, even more preferably 0.1-5% by weight, based on the total weight of all solid components of the layer.

Preferable examples of polysiloxane compounds are those polysiloxanes having a substituent at at least one position of an arbitrary terminal of a compound chain containing a plurality of dimethylsiloxy units as a repeating unit and side branches. The compound chain containing repeating dimethylsiloxy units may contain any other structural units other than dimethylsiloxy units. Preferably, the compound contains multiple identical or different substituents. Preferable examples of substituents are any of acryloyl, methacryloyl, vinyl, aryl, cinnamoyl, epoxy, oxetanyl, hydroxyl, fluoroalkyl, polyoxyalkylene, carboxyl and amino groups. substituents. Although not specifically defined, the molecular weight of the compound is preferably at most 100,000, more preferably at most 50,000, most preferably 3,000-30,000. Also not particularly limited, the polysiloxane atom content in the polysiloxane compound is preferably at least 18.0% by weight, more preferably 25.0-37.8% by weight, most preferably 30.0-37.0% by weight. Preferred examples of polysiloxane compounds are Shin-etsu Chemical's X-22-174DX, X-22-2426, X-22-164B, X22-164C, X-22-170DX, X-22-176D, X- 22-1821 (all trade names), Chisso's FM-0725, FM-7725, FM-4411, FM-5521, FM-6621, FM-1121 and Gelest's DMS-U22, RMS-033, RMS-083 , UMS-182, DMS-H21, DMS-H31, HMS-301 (all trade names), however, the present invention is not limited thereto.

The fluorine-containing compound is preferably a compound having a fluoroalkyl group. Preferably, the fluoroalkyl group has 1-20 carbon atoms, more preferably 1-10 carbon atoms, and may have a linear structure (eg, -CF ₂ CF ₃ , CH ₂ (CF ₂ ) ₄ H, -CH ₂ (CF ₂ ) ₈ CF ₃ , -CH ₂ CH ₂ (CF ₂ ) ₄ ), or branched structures (eg, -CH(CF ₃ ) ₂ , -CH ₂ CF(CF ₃ ) ₂ , -CH(CH ₃ ) CF ₂ CF ₃ , -CH(CH ₃ )(CF ₂ ) ₅ CF ₂ H), or an alicyclic structure (preferably 5-membered or 6-membered, eg, perfluorocyclohexyl, perfluorocyclopentyl, or alkyl substituted by any of these groups); or it may have an ether linkage (for example, -CH ₂ OCH ₂ CF ₂ CF ₃ , -CH ₂ CH ₂ OCH ₂ C ₄ F ₈ H, -CH ₂ CH ₂ OCH ₂ CH ₂ C ₂ F ₁₇ , -CH ₂ CH ₂ OCF ₂ CF ₂ OCF ₂ CF ₂ H). This compound may have a plurality of fluoroalkyl groups in one molecule.

Preferably, the fluorine-containing compound contains a substituent which facilitates adhesion to or is compatible with the film of the low refractive index layer. Also preferably, the compound has a plurality of such substituents, which may be the same or different. Preferable examples of the substituent are acryloyl, methacryloyl, vinyl, aryl, cinnamoyl, epoxy, oxetanyl, hydroxyl, polyoxyalkylene, carboxyl and amino groups. The fluorine-containing compound may be a polymer or oligomer with a compound not containing fluorine atoms, and its molecular weight is not particularly limited. Also not particularly limited, the content of fluorine atoms in the fluorine-containing compound is preferably at least 20% by weight, more preferably 30-70% by weight, most preferably 40-70% by weight. Preferred examples of fluorine-containing compounds are Daikin's R-2020, M-2020, R-3833, M-3833 (all trade names), Dai-Nippon Ink's MegafacF-171, F-172, F-179A, Diffenser MCF-300 (both trade names), however, the present invention is not limited thereto.

Examples of the fluoroalkyl polysiloxane compound are Gelest's FMS121, FMS123, FMS131, FMS141, FMS221, however, the present invention is not limited thereto. Although not particularly limited, preferred examples of the fluorine content and polysiloxane content of the compound, and the substituent in the compound molecule may be the same as described above for the polysiloxane compound and the fluorine-containing compound.

The surface free energy lowering compound preferably has at least one binder-reactive group in the molecule. Preferable examples of the reactive group are thermosetting active hydrogen atoms, hydroxyl groups, melamine, active energy ray-curable (meth)acryloyl groups, and epoxy groups. Among them, melamine or (meth)acryloyl is particularly preferable.

Dust inhibitors and antistatic agents, such as known cationic surfactants or polyoxyalkylene compounds, may be added to the low refractive index layer to make the layer dustproof and antistatic. Silicone compounds and fluorine-containing compounds may contain structural units of dust inhibitors and antistatic agents as part of their function. When they are added to the layer as additives, their amount is preferably 0.01-20% by weight, more preferably 0.05-10% by weight, even more preferably 0.1-5% by weight of the total solid component weight of the low-refractive index layer . Preferable examples of the compound are Dai-Nippon Ink's Megafac F-150 (trade name) and Toray-Dow Corning's SH-3747 (trade name), however, the present invention is not limited thereto.

Adhesives usable for the low refractive index layer of the antireflection film of the present invention are described. The binder is preferably a polymer having a saturated hydrocarbon chain or a polyether chain as its main chain structure, more preferably a polymer having a saturated hydrocarbon chain as its main chain structure. It is also preferred that the binder polymer has a crosslinked structure.

The binder polymer having a saturated hydrocarbon chain as a main chain structure is preferably a polymer of an ethylenically unsaturated monomer. The binder polymer having a saturated hydrocarbon chain as a main chain structure and having a crosslinked structure is preferably a (co)polymer of a monomer having two or more ethylenically unsaturated groups.

Monomers having two or more ethylenically unsaturated groups include polyols and (meth)acrylic esters (e.g., ethylene glycol di(meth)acrylate, 1,4-cyclohexane di Acrylates, Pentaerythritol Tetra(meth)acrylate, Pentaerythritol Tri(meth)acrylate, Trimethylolpropane Tri(meth)acrylate, Trimethylolethane Tri(meth)acrylate, Dipentaerythritol Tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,2,3-cyclohexane tetramethacrylate, polyurethane polyacrylate, polyester polyacrylates), vinylbenzene and its derivatives (for example, 1,4-divinylbenzene, 2-acryloylethyl 4-vinylbenzoate, 1,4-divinylcyclohexanone) , vinylsulfones (for example, divinylsulfone), acrylamides (for example, methylenebisacrylamide), and methacrylamides. Two or more of these monomers may be used in combination. In this specification, "(meth)acrylate" means "acrylate or methacrylate".

The polymerization of these monomers having ethylenically unsaturated groups can be carried out by exposure to active energy rays or by exposure to heat in the presence of an optical radical initiator or a thermal radical initiator.

Therefore, a coating liquid containing an ethylenically unsaturated monomer, an optical radical initiator or a thermal radical initiator, matte particles, and an inorganic filler is prepared, and the coating liquid is applied to a transparent support, and then Polymerized and cured by exposure to active energy rays or exposure to heat to form an antireflective film.

Optical free radical initiators include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2, 3-dialkyldiketone compounds, disulfide compounds, fluoroamine compounds, and aromatic sulfonium compounds. Examples of acetophenones are 2,2-diethoxyacetophenone, p-dimethylacetophenone, 1-hydroxydimethyl phenyl ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl Base-4-methylthio-2-morpholinophenyl ethyl ketone, and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone. Examples of benzoins are benzoin besylate, benzoin tosylate, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether. Examples of benzophenones are benzophenone, 2,4-dichlorobenzophenone, 4,4-dichlorobenzophenone, and p-chlorobenzophenone. An example of phosphine oxides is 2,4,6-trimethylbenzoyldiphenylphosphine oxide. Various examples of these compounds are described in the Newest UV Curing Technology (p.159, published by Kazuhiro Takatsu, published by Gijutsu Joho Kyokai, 1991), and they can be used in the present invention. A preferred example of a commercially available, photocleavage optical radical polymerization initiator is Ciba Specialty Chemicals' Irgacure (651, 184, 907). Preferably, the photopolymerization initiator is used in an amount of 0.1-15 parts by weight, more preferably 1-10 parts by weight, relative to 100 parts by weight of the polyfunctional monomer. A photosensitizer may be added to the photopolymerization initiator. Examples of photosensitizers are n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone and thioxanthone.

Thermal free radical initiators include organic or inorganic peroxides, and organic azo and diazo compounds. Specifically, organic peroxides include benzoyl peroxide, halogenated benzoyl peroxide, lauroyl peroxide, acetyl peroxide, dibutyl peroxide, cumene hydroperoxide, butyl hydroperoxide; Peroxides include hydrogen peroxide, ammonium persulfate, potassium persulfate; azo compounds include 2-azobisisobutyronitrile, 2-azobispropionitrile, 2-azobiscyclohexane-dinitrile; and Diazo compounds Diazoaminobenzene and p-nitrobenzene-diazo compounds.

The polymer having a polyether main chain structure used as the binder of the low refractive index layer is preferably a ring-cleavage polymer of a polyfunctional epoxy compound. The ring-cleavage polymerization of the polyfunctional epoxy compound can be carried out by exposure to active energy rays or exposure to heat in the presence of an optical or thermal acid generator. Therefore, a coating solution containing a multifunctional epoxy compound, an optical acid generator or a thermal acid generator, matte particles, and an inorganic filler is prepared; and the coating solution is applied to a transparent support, and then exposed to Polymerization and curing under active energy rays or exposure to heat form an antireflective film.

Instead of, or in addition to, a monomer having two or more ethylenically unsaturated groups for preparing a binder polymer having a saturated hydrocarbon chain as a main chain structure and having a crosslinked structure, A monomer having a crosslinking functional group may be used in order to introduce the crosslinking functional group into the polymer, and through a reaction of the crosslinking functional group, a crosslinking structure may be introduced into the binder polymer.

Examples of the crosslinking functional group are isocyanate group, epoxy group, aziridinyl group, oxazoline group, aldehyde group, carbonyl group, hydrazine group, carboxyl group, hydroxymethyl group and activated methylene group. Vinylsulfonic acids, anhydrides, cyanoacrylate derivatives, melamines, etherified methylols, esters and urethanes, and metal alkoxides (e.g. tetramethoxysilane) can also be used As a monomer to introduce a crosslinked structure into a polymer. It is also possible to use functional groups which can crosslink after a decomposition reaction, for example blocked isocyanate groups. Therefore, in the present invention, the crosslinking functional group may not be directly reactive, but may become reactive after decomposition. After coating on the support, the binder polymer with such cross-linking functional groups can be coated and heated to form the desired cross-linking structure.

Not particularly limited, the binder for reducing the surface free energy used in the low refractive index layer of the antireflection film of the present invention may be when the binder is added to a monomer such as typically DPHA by curing an alkyl acrylate monomer. Either one can significantly reduce the surface free energy of the layer when formed on the layer. Particularly preferably, the adhesive is such that the surface free energy of the layer cured and formed solely by the adhesive is at most 30 mN/m, more preferably at most 25 mN/m, even more preferably at most 20 mN/m. The adhesive is preferably a compound containing at least one group selected from the group consisting of fluoroalkyl, dimethylsiloxane and polydimethylsiloxane (polysiloxane) groups. Prior to curing, the binder may be monomeric or polymeric, or may be a mixture of monomers and polymers, or may be a mixture of compounds.

Preferred examples of the surface free energy-reducing binder used for the low-refractive index layer are described. The surface free energy reducing binder is preferably a low refractive index binder such as a fluoropolymer. The fluoropolymer preferably has a kinetic friction coefficient of 0.03-0.15 and a contact angle with water of 90-120°C, and is preferably crosslinkable when exposed to active energy rays.

The low refractive index layer of the antireflection film of the present invention preferably contains a fluorine-containing compound. Specifically, the low refractive index layer of the present invention is preferably formed of a cured fluororesin that is mainly a thermosetting or ionizing radiation-curable crosslinked fluorine-containing compound.

In the present invention, the term "mainly fluorine-containing compounds" means that the content of fluorine-containing compounds in the low refractive index layer is at least 50 wt%, more preferably at least 60 wt% of the total weight of the low refractive index layer.

Preferably, the fluorine-containing compound has a refractive index of 1.35-1.50, more preferably 1.36-1.47. Also preferably, the fluorine-containing compound has a fluorine atom content of 35 to 80% by weight.

Fluorine-containing compounds include fluorine-containing polymers, fluorine-containing surfactants, fluorine-containing ethers, fluorine-containing silane compounds, fluorine-containing monomers and fluorine-containing oligomers, all of which can be called fluorine-containing compounds. Specifically, these compounds are listed in, for example, paragraphs [0018]-[0026] of JP-A 9-222503, paragraphs [0019]-[0030] of JP-A11-38202, and paragraphs [0027] of JP-A 2001-40284. - paragraphs [0028] are described, and they can be used in the present invention.

(fluoropolymer)

The fluorine-containing polymer is preferably a copolymer comprising repeating structural units containing fluorine atoms, repeating structural units containing crosslinking or polymerizing functional groups, and other repeating structural units of any other substituents. Particularly preferred are copolymers of fluoromonomers and comonomers imparting crosslinking groups thereto, or ie, fluoropolymers containing curable reactive groups serving as crosslinking and polymerizing functional groups. Other fluoropolymers copolymerized with any other monomers may also be used in the present invention.

The crosslinking or polymerizing functional groups may be any known ones.

Examples of crosslinking functional groups are isocyanate groups, epoxy groups, aziridinyl groups, oxazoline groups, aldehyde groups, carbonyl groups, hydrazine groups, carboxyl groups, hydroxymethyl groups, and activated methylene groups. Furthermore, vinylsulfonic acids, acid anhydrides, cyanoacrylate derivatives, melamines, etherified methylols, esters and urethanes, and metal alkoxides (such as tetramethoxysilane) are also Can be used as a monomer to introduce a crosslinked structure into the polymer. It is also possible to use functional groups which can be crosslinked after a decomposition reaction, for example blocked isocyanate groups can also be used. Therefore, in the present invention, the crosslinking functional group may not be directly reactive, but may become reactive after decomposition. After coating on the support, the compound with such cross-linking functional groups can be coated and heated to form the desired cross-linking structure.

Polymeric functional groups include radically polymerizable groups and cationically polymerizable groups.

Radical polymerizable groups (eg, (meth)acryloyl, styryl, vinyloxy) and cationically polymerizable groups (eg, epoxy, thioepoxy, oxetanyl) are preferred.

Other repeating structural units are preferably those formed from hydrocarbon copolymer components for dissolution in a solvent. Preferably, the fluoropolymer contains about 50% by weight of the polymer of such structural units. Also preferably, a fluoropolymer is mixed with a polysiloxane compound.

The polysiloxane compound is a compound having a polysiloxane structure. Preferably, it contains a curable functional group or a polymerizable functional group in the polymer chain, and it can be cross-linked to have a cross-linked structure in the film. For example, the present invention can use commercially available reactive polysiloxanes such as Silaplane (manufactured by Chisso), and compounds having silanol groups at both ends of their polysiloxane structures as in JP-A-11-258403.

The crosslinking or polymerization reaction of the fluorine-containing polymer having a crosslinking and polymerizing group is preferably performed while the curable composition is applied to the support to form the outermost layer or after the application thereof, and the layer can be formed by Obtained by exposure to light or heat.

In this step, a polymerization initiator and a sensitizer may be used, and they may be the same as those used for the light-diffusing layer.

Without particular limitation, comonomers include, for example, olefins (e.g., ethylene, propylene, isoprene, vinyl chloride, vinylidene chloride), acrylates (e.g., methyl acrylate, ethyl acrylate, 2- ethylhexyl), methacrylates (e.g. methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene glycol dimethacrylate), styrene derivatives (e.g. benzene Ethylene, divinylstyrene, vinyltoluene, α-methylstyrene), vinyl ethers (e.g., methyl vinyl ether), vinyl esters (e.g., vinyl acetate, vinyl propionate, Vinyl cinnamate), acrylamides (for example, N-tert-butylacrylamide, N-cyclohexylacrylamide), methacrylamides, acrylonitrile derivatives.

For example, a curing agent may be suitably added to the polymer, as in JP-A-10-25388 and JP-A-10-147739.

For the low refractive index layer, it is also preferable to use a sol-gel cured film formed by condensation curing an organometallic compound such as a silane coupling agent and a silane coupling agent having a specific fluorine-containing hydrocarbon group in the presence of a catalyst.

For example, there are mentioned polyfluoroalkyl-containing silane compounds and their partial hydrolysis condensates (for example, compounds described in JP-A-58-142958, 58-147483, 58-147484); JP-A-9 - Silane coupling agents containing perfluoroalkyl groups described in 157582; silyl compounds containing fluorine-containing long-chain groups and multi-perfluoroalkyl ether groups (for example, JP-A-2000-117902, 2001 -48590, compounds described in 2002-53804).

The catalyst used in the present invention may be any known compound, and preferred examples thereof are described in the above-mentioned documents.

Fluoropolymers used in the low refractive index layer include hydrolytic dehydration condensates of perfluoroalkyl-containing silane compounds (for example, heptadecafluoro-1,1,2,2-tetrahydrodecyl)triethoxysilane ), and a fluorine-containing copolymer containing a fluorine-containing monomer unit and a structural unit for imparting crosslinking reactivity to the polymer as its constituents.

Specific examples of fluorine-containing monomers include fluoroolefins (e.g., fluoroethylene, difluoroethylene, tetrafluoroethylene, perfluoro-octylethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3- Dioxole), partially or fully fluorinated alkyl ester derivatives of (meth)acrylic acid (for example, Biscoat6FM (manufactured by OsakaYuki Kagaku), M-2020 (manufactured by Daikin)), and fully and partially fluorinated of vinyl ethers. Perfluoroolefins are preferred; hexafluoropropylene is more preferred from the viewpoint of its refractive index, solubility, transparency and availability.

The structural unit for imparting crosslinking reactivity to the polymer is, for example, a structural unit formed by polymerization of a monomer inherently having a self-crosslinking functional group in the molecule, such as glycidyl (meth)acrylate or glycidylvinyl base ethers; structural units formed by the polymerization of monomers having carboxyl, hydroxyl, amino and sulfo groups (for example, (meth)acrylic acid, hydroxymethyl (meth)acrylate, hydroxyalkyl (meth)acrylate, acrylic acid allyl ester, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, maleic acid, crotonic acid); through the polymerization reaction, a structure composed of a cross-linking reactive group such as (meth)acryloyl group is introduced into these structural units unit (for example, these groups can be added by reacting acryloyl chloride with a hydroxyl group).

Particularly useful fluoropolymers for the low refractive index layer of the present invention are random copolymers of perfluoro-olefins and vinyl ethers or vinyl esters. It is especially preferred that the polymer has groups that themselves can undergo a crosslinking reaction (e.g., free radically reactive groups such as (meth)acryloyl groups, and ring-cleaving polymeric groups such as epoxy or oxetanyl groups) . Preferably, the amount of polymer units containing crosslinking reactive groups is 5-70 mol%, more preferably 30-60 mol%, of all polymer units in the polymer.

A preferred embodiment of the copolymer (fluoropolymer) used for the low refractive index layer is a polymer of the following formula (1):

In formula (1), L represents a linking group with 1-10 carbon atoms, preferably 1-6 carbon atoms, more preferably 2-4 carbon atoms, and it may have a linear structure, or branched structure, or a ring structure, and it may contain heteroatoms selected from O, N and S. Preferred examples of L are ^* -(CH ₂ ) ₂ -O- ^** , ^* -(CH ₂ ) ₂ -NH- ^** , ^* -(CH ₂ ) ₄ -O- ^** , ^* -(CH ₂ ) ₆ -O- ^** , ^* -(CH ₂ ) ₂ -O-(CH ₂ ) ₂ -O- ^** , ^* -CONH-(CH ₂ ) ₃ -O- ^** , ^* -CH ₂ CH(OH )CH ₂ -O- ^** , ^* -CH ₂ CH ₂ OCONH(CH ₂ ) ₃ -O- ^** (where ^* represents the connection position of the main chain structure end; ^** represents the connection end of the (meth)acryloyl terminal) . m stands for 0 or 1.

In formula (1), X represents a hydrogen atom or a methyl group. From the viewpoint of curing reactivity of the polymer, X is preferably a hydrogen atom.

In formula (1), A represents a repeating unit derived from a vinyl monomer, and, without particular limitation, it may be any constituent of a monomer copolymerizable with hexafluoropropylene. From the point of view of the adhesion of the polymer to the substrate, its Tg (which is beneficial to the hardness of the film), its solubility in solvents, its transparency, its lubricity, and its dust and stain resistance, can be suitably Choose unit A. Depending on the purpose of the polymer, one or more different types of vinyl monomers can form the repeat unit A.

Preferred examples of vinyl monomers are vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, t-butyl vinyl ether, cyclohexyl vinyl ether, isopropyl vinyl ether, hydroxyethyl vinyl ether, Ether, hydroxybutyl vinyl ether, glycidyl vinyl ether, allyl vinyl ether; vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate; (meth)acrylates such as Methyl (meth)acrylate, ethyl (meth)acrylate, hydroxyethyl (meth)acrylate, glycidyl methacrylate, allyl (meth)acrylate, (meth)acryloxy Propyltrimethoxysilane; styrene derivatives such as styrene, p-hydroxymethylstyrene; unsaturated carboxylic acids and their derivatives such as crotonic acid, maleic acid, itaconic acid. More preferred are vinyl ether derivatives and vinyl ester derivatives; even more preferred are vinyl ether derivatives.

x, y, and z each refer to mol% of constituents, and satisfy the following formula: 30≤x≤60, 5≤y≤70, 0≤z≤65. Preferably, 35≤x≤55, 30≤y≤60, 0≤z≤25; more preferably 40≤x≤55, 40≤y≤55, 0≤z≤10.

A more preferred embodiment of the copolymer used in the low refractive index layer of the antireflection film of the present invention is the polymer of the following formula (2):

In formula (2), X, x and y have the same meanings as X, x and y in formula (1), and their preferred ranges are the same as in formula (1). n represents an integer of 2≤n≤10, preferably 2≤n≤6, more preferably 2≤n≤4. B represents a repeating unit derived from a vinyl monomer, and it may consist of a single component or multiple components. Examples refer to those mentioned above for A in formula (1) herein. z1 and z2 each refer to the mol% of the repeating unit, and satisfy 0≤z1≤65 and 0≤z2≤65. Preferably, 0≤z1≤30 and 0≤z2≤10; more preferably 0≤z1≤10 and 0≤z2≤5.

For example, the copolymer of formula (1) or (2) can be produced by introducing a (meth)acryloyl group into a copolymer containing a hexafluoropropylene component and a hydroxyalkyl vinyl ether component according to any of the methods described above.

Preferred examples of the copolymer used in the present invention are described below, however, the present invention is not limited thereto.

*Represents the end of the polymer backbone

*Represents the end of the polymer backbone

* represents the polymer main chain end, ** represents the acryloyl end

x the y z Rf L Number average molecular weight Mn(×10 ⁴ ) P-34P-35P-36 606040 403060 0100 -CH ₂ CH ₂ C ₈ F ₁₇ -n-CH ₂ CH ₂ C ₄ F ₈ Hn-CH ₂ CH ₂ C ₆ F ₁₂ H _-CH ₂ CH ₂ O-_-CH ₂ CH ₂ O-_-CH ₂ CH ₂ CH ₂ CH ₂ O- 11304.0

*Represents the end of the polymer backbone

x the y z no Rf Number average molecular weight Mn(×10 ⁴ ) P-37P-38P-39P-40 50403060 50557040 0500 2242 -CH ₂ C ₄ F ₈ Hn-CH ₂ C ₄ F ₈ Hn-CH ₂ C ₈ F ₁₇ -n-CH ₂ CH ₂ C ₈ F ₁₆ Hn 5.04.0105.0

The copolymer used in the present invention can be produced by preparing a precursor such as a hydroxyl group-containing polymer according to various polymerization methods such as solution polymerization, precipitation polymerization, suspension polymerization, bulk polymerization, and emulsion polymerization, and then reacting the above-mentioned polymer A (meth)acryloyl group is introduced thereinto. The polymerization reaction can be carried out in any known batch, or semi-continuous or continuous operation.

To start the polymerization, a method with a free radical initiator, or a method of exposing the system to light or radiation can be used.

The polymerization method and polymerization initiation method are described, for example, in Teiji Tsuruta, Methods of Polymer Synthesis, Revised Edition (published by Nikkan Kogyo Shinbun, 1971); Takayuki Ohtsu & Masaetsu Kinoshita, Experimental Methods of Polymer Synthesis (published by Kagaku Dojin, 1972, pp.124-154) is described in .

Among the above-mentioned polymerization methods, a solution polymerization method using a radical initiator is particularly preferable. Solvents that can be used in this solution polymerization process include, for example, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, tetrahydrofuran, dioxane, N,N-di Methylformamide, N,N-dimethylacetamide, benzene, toluene, acetonitrile, methylene chloride, chloroform, dichloroethane, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol . One or more of these various organic solvents may be used alone or in combination, or a mixed solvent thereof with water may also be used.

The polymerization temperature must be set according to the molecular weight of the polymer being prepared and the type of initiator used. It may be from 0°C or lower to 100°C or higher, but preferably 50-100°C.

The reaction pressure can be appropriately determined, but usually falls within the range of 1-100 kg/cm ² , preferably 1-30 kg/cm ² . Reaction times may fall within the range of around 5-30 hours.

The solvent used for the reprecipitation of the obtained polymer is preferably isopropanol, hexane, methanol or the like.

A method for determining the segregation of polysiloxane or fluoroalkyl groups on the surface of a low refractive index layer is described. The photoelectric spectrum, ^Si2P , Fls and Cls; and calculate the spectral intensity ratios Si2P/Cls (=Si(a)) and Fls/Cls (=F(a)). Using the ion etching device of equipment ESCA-3400 (ion gun, voltage 2kV, current 20mA), cut the low refractive index layer of the sample to a height of 1/5 (5%) of its original height, and measure 80% of the layer Photospectra, Si2P, Fls, and Cls at depth positions; and calculated spectral intensity ratios Si2P/Cls (=Si(b)) and Fls/Cls (=F(b)). The intensity changes, Si(a)/Si(b) and F(a)/F(b) before and after the etching treatment were obtained. Therefore, by the change of the Si2P/Cls ratio and the Fls/Cls ratio before and after the etching treatment (the photoelectric spectral intensity ratio of the outermost surface of the low-refractive index layer/in the layer from the 80% depth of the outermost surface of the low-refractive index layer The photoelectric spectral intensity ratio) can determine the degree of surface segregation. Fls and Cls are the intensity readings of the peaks of the photospectra. In the case of Si2p, the intensity of the peak position of the Si atom derived from polysiloxane (polydimethylsiloxane), where the binding energy is around 105 eV, was used for the intensity ratio calculation, and it was compared with that obtained from the inorganic dimethicone The Si atoms of the silicon oxide particles are different. Under different etching conditions, carry out the preliminary test of the gradual etching of the surface of the low refractive index layer in different samples, and based on the etching conditions to reach the underlying hard coating or high refractive index layer, measure the depth of the low refractive index layer reaching 80%. condition. When only the surface properties are controlled, the surface segregation compound (i.e., a compound that lowers the surface free energy) described in this specification can be appropriately used, and only the desired components can be placed on the surface of the layer, and as a result, it is not necessary to The surface properties are independently controlled by the internal properties of the film.

The hydrolyzate of the organosilane compound and/or its partial condensate, or ie, the sol component (which will be applied later herein) for use in the present invention will be described in detail later in this specification.

The organosilane compound is represented by the following formula (A):

(R ¹⁰ ) _m Si(X) _4-m

In formula (A), R ¹⁰ represents a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. Alkyl groups include methyl, ethyl, propyl, isopropyl, hexyl, tert-butyl, sec-butyl, hexyl, decyl, hexadecyl. The alkyl group preferably has 1-30 carbon atoms, more preferably 1-16 carbon atoms, even more preferably 1-6 carbon atoms. Aryl includes phenyl, naphthyl, and preferably phenyl.

X represents a hydroxyl group or a hydrolyzable group. Hydrolyzable groups include, for example, alkoxy groups (preferably having 1-5 carbon atoms, e.g., methoxy, ethoxy), halogen atoms (e.g., Cl, Br, I), and R ^COO (where R ² is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; examples thereof are CH ₃ COO, C ₂ H ₅ COO). Preferably, it is alkoxy, more preferably methoxy or ethoxy. m represents an integer of 1-3. If there are multiple R ¹⁰ or X in the compound, they may be the same or different. m is preferably 1 or 2, more preferably 1.

There is no particular limitation, and substituents in R ¹⁰ include, for example, halogen atoms (for example, fluorine atoms, chlorine atoms, bromine atoms), hydroxyl groups, mercapto groups, carboxyl groups, epoxy groups, alkyl groups (for example, methyl groups, ethyl groups) , isopropyl, propyl, tert-butyl), aryl (for example, phenyl, naphthyl), aromatic heterocyclic group (for example, furyl, pyrazolyl, pyridyl), alkoxy (for example, methyl oxy, ethoxy, isopropoxy, hexyloxy), aryloxy (for example, phenoxy), alkylthio (for example, methylthio, ethylthio), arylthio (for example, benzene thio), alkenyl (e.g., vinyl, 1-propenyl), acyloxy (e.g., acetoxy, acryloxy, methacryloxy), alkoxycarbonyl (e.g., methacryloxy) oxycarbonyl, ethoxycarbonyl), aryloxycarbonyl (for example, phenoxycarbonyl), carbamoyl (for example, carbamoyl, N-methylcarbamoyl, N,N-dimethylcarbamoyl, N -methyl-N-octylcarbamoyl), amido (eg, acetamido, benzamido, acrylamido, methacryloylamino). These substituents may also be substituted. If there are multiple R ¹⁰ in the compound, at least one R ¹⁰ is preferably substituted alkyl or substituted aryl. In particular, organosilane compounds having vinyl-polymeric substituents of formula (B) are preferably used in the present invention.

In formula (B), R ¹ represents a hydrogen atom, or a methyl group, a methoxy group, an alkoxycarbonyl group, a cyano group, a fluorine atom or a chlorine atom. Alkoxycarbonyl includes methoxycarbonyl and ethoxycarbonyl. Preferably, ^R is a hydrogen atom, methyl, methoxy, methoxycarbonyl, cyano, fluorine or chlorine atom, more preferably a hydrogen atom, methyl, methoxycarbonyl, fluorine or chlorine atom, even More preferably, it is a hydrogen atom or a methyl group. Y represents a single bond or an ester group, amido group, ether group or urea group. Preferably, Y is a single bond, an ester group or an amido group, more preferably a single bond or an ester group, particularly preferably an ester group.

L represents a divalent linkage chain. Specifically, it represents a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted alkylene group with a linking group (e.g., ether, ester, amido) therein, Or a substituted or unsubstituted arylene group having a linking group therein; preferably, it is a substituted or unsubstituted alkylene group having 2-10 carbon atoms, a substituted or unsubstituted group having 6-20 carbon atoms An arylene group, or an alkylene group having 3-10 carbon atoms and having a linking group therein; more preferably an unsubstituted alkylene group, an unsubstituted arylene group, or an alkylene group having an ether or ester linking group therein An alkylene group; particularly preferred is an unsubstituted alkylene group, or an alkylene group having an ether or ester linkage therein. Their substituents include halogen atoms, hydroxyl groups, mercapto groups, carboxyl groups, epoxy groups, alkyl groups, and aryl groups, and these substituents may also be substituted.

n stands for 0 or 1. If there are multiple Xs in the compound, they may be the same or different. n is preferably 0. R ¹⁰ has the same meaning as in formula (A), and is preferably a substituted or unsubstituted alkyl group, or an unsubstituted aryl group, more preferably an unsubstituted alkyl group or an unsubstituted aryl group. X has the same meaning as in formula (A), and is preferably a halogen atom, a hydroxyl group, or an unsubstituted alkoxy group, more preferably a chlorine atom, a hydroxyl group, or an alkoxy group having 1 to 6 carbon atoms, particularly preferably a hydroxyl group or Alkoxy having 1 to 3 carbon atoms, even more preferably methoxy.

Two or more different types of compounds of formula (A) and formula (B) may be mixed for use in the present invention. Specific examples of compounds of formula (A) and formula (B) are shown below, however, the present invention is not limited thereto.

Among these examples, (M-1), (M-2) and (M-5) are particularly preferred.

(acid catalyst, metal chelate)

It is desirable to prepare hydrolyzates and/or condensates (sol components) of organosilanes in the presence of a catalyst. Catalysts include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid; organic acids such as oxalic acid, acetic acid, formic acid, methanesulfonic acid, toluenesulfonic acid; inorganic bases such as sodium hydroxide, potassium hydroxide, ammonia; organic bases such as triethylamine, pyridine; and metal alkoxides such as aluminum triisopropoxide, zirconium tetrabutoxide. An acid catalyst (inorganic acid, organic acid) and/or a metal chelate is used in the present invention in view of production stability and storage stability of a liquid of inorganic oxide fine particles. The inorganic acid is preferably hydrochloric acid or sulfuric acid; and the organic acid preferably has an acid dissociation constant (pKa value at 25°C) in water of not more than 4.5. More preferred are hydrochloric acid, sulfuric acid, and organic acids having an acid dissociation constant in water of at most 3.0; especially preferred are hydrochloric acid, sulfuric acid, and organic acids with an acid dissociation constant in water of at most 2.5; even more preferred are the acid dissociation constants in water of at most 2.5 organic acid; further more preferably methanesulfonic acid, oxalic acid, phthalic acid and malonic acid; particularly preferably oxalic acid.

When the hydrolyzable group of the organosilane is an alkoxy group and the acid catalyst is an organic acid, the carboxyl group or sulfo group of the organic acid can provide a proton, so the amount of water added can be reduced. Specifically, the amount of water added to the reaction system may be 0-2 mol, preferably 0-1.5 mol, more preferably 0-1 mol, even more preferably 0-0.5 mol, relative to 1 mol of alkoxide groups in the organosilane. When alcohol is used as a solvent, an embodiment in which substantially no water is added to the system is also preferred.

Describe the amount of acid catalyst used. When the acid catalyst is an inorganic acid, relative to the hydrolyzable group, the amount of the inorganic acid can be 0.01-10mol, preferably 0.1-5mol; but when the acid catalyst is an organic acid, its most preferred amount varies with the amount added to the system The amount of water varies. Specifically, when water is added to the system, the organic acid may be added in an amount of 0.01-10 mol%, preferably 0.1-5 mol%, relative to the hydrolyzable group. However, when substantially no water is added, the organic acid may be added in an amount of 1-500 mol%, preferably 10-200 mol%, even more preferably 20-200 mol%, even more preferably 50-150 mol%, relative to the hydrolyzable group, Even more preferably 50-120 mol%.

This treatment can be achieved by stirring the system at 15-100°C, and the organosilane is properly controlled according to its reactivity.

Without particular limitation, any metal chelate compound having a central metal selected from Zr, Ti, or Al may be preferably used in the present invention. Within this range, two or more different types of metal chelates may be used in combination. Specific examples of metal chelates used in the present invention are zirconium chelates such as zirconium tri-n-butoxyethylacetoacetate, zirconium di-n-butoxybis(ethylacetoacetate), zirconium n-butoxytris(ethylacetoacetate), zirconium tetra(n-propylacetoacetate), zirconium tetra(n-propylacetoacetate), zirconium tetrakis(acetylacetoacetate), zirconium tetra(ethylacetoacetate); titanium chelate compounds such as diisopropoxybis(ethylacetoacetate) Titanium acetate, diisopropoxybis(acetoacetate)titanium, diisopropoxybis(acetylacetonate)titanium; aluminum chelate compounds such as aluminum diisopropoxyethylacetoacetate, diisopropoxy Aluminum acetylacetonate, aluminum isopropoxybis(ethylacetoacetonate), aluminum isopropoxybis(acetylacetonate), aluminum tris(ethylacetoacetonate), aluminum tris(acetylacetonate), monoacetylacetonate-di Aluminum (ethylacetoacetate).

Among the metal chelate compounds, zirconium tri-n-butoxyethylacetoacetate, titanium diisopropoxybis(acetylacetonate), aluminum diisopropoxyethylacetoacetate, and aluminum tris(ethylacetoacetate) are preferable. One or more of these metal chelates may be used singly or in combination. Partial hydrolysates of these metal chelate compounds can also be used.

In the present invention, from the viewpoint of the condensation speed and mechanical strength of the polymer film, the ratio of the metal chelate used to the organosilane is preferably 0.01-50% by weight, more preferably 0.1-50% by weight, even more preferably 0.5-10% by weight. % by weight is used.

In the present invention, when the hydrolyzate and partial condensate of the organosilane compound are prepared by treating in the presence of the above-mentioned metal chelate, it is desirable that at least any β-diketone compound and β-diketone ester compound be present in the above-mentioned curable composition. They serve as stability improvers for the curable compositions of the invention. Specifically, it is considered that the compound can coordinate with the metal atom in the above-mentioned metal chelate compound (zirconium, titanium or aluminum compound), thereby delaying the formation of the hydrolyzate and partial condensate of the organosilane compound promoted by the above-mentioned metal chelate compound. Condensation, thereby improving the storage stability of the curable composition. As for the β-diketone compound and β-diketone ester compound, the ligands used in the specific examples of the metal chelate compound described above in this specification are preferred.

Specific examples of β-diketone compounds and β-diketone ester compounds include acetylacetone, methyl acetoacetate, ethyl acetoacetate, n-propyl acetoacetate, isopropyl acetoacetate, n-butyl acetoacetate, acetoacetate sec-butyl ester, tert-butyl acetoacetate, 2,4-hexanedione, 2,4-heptanedione, 3,5-heptanedione, 2,4-octanedione, 2,4-nonanedione, 5-Methylhexanedione. Among them, ethyl acetoacetate and acetylacetone are preferred; acetylacetone is more preferred. One or more of these β-diketone compounds and β-diketone ester compounds may be used in the present invention singly or in combination. In the present invention, the amount of the β-diketone compound and the β-diketone ester compound is preferably at least 2 mol%, more preferably 3-20 mol, relative to 1 mol of the metal chelate compound, from the viewpoint of storage stability of the composition.

The amount of the organosilane compound or its sol component in the composition (the total amount when both are added) is preferably 0.1 to 50% by weight, more preferably 0.5 to 20% by weight, of the total solid content of the low refractive index layer , most preferably 1-10% by weight.

When the organosilane compound is directly added to the low refractive index layer as it is, the organosilane compound may be partially evaporated while drying to remove the solvent. In this case, therefore, a relatively large amount of the compound must be added to the layer. On the other hand, when the compound is added thereto as its sol component, the amount thereof can be relatively reduced. This is advantageous since it is easy to control the properties of the layer, such as the refractive index.

Organosilane compounds preferably used in the third embodiment of the present invention are organosilane compounds of the following formula (A1):

(R ¹⁰¹ ) _m Si(X) _4-m

wherein R ¹⁰¹ represents an alkyl group; X represents a hydroxyl group or a hydrolyzable group; and m represents an integer of 1-3.

The above-mentioned organosilane compound or its sol component is preferably mixed with the above-mentioned polyfunctional (meth)acrylate monomer for improving the scratch resistance of the polymer film, especially for improving the anti-reflection performance and durability of the polymer film. Abrasion.

The organosilane compound or its sol component is in a curable composition, and the curable composition is coated on a substrate, dried and exposed to ionizing radiation or heat, or both, to make the curable composition Polymerized or condensed and cured to form a low refractive index layer in which the organosilane compound or sol component thereof functions as a binder. When the organosilane compound or its sol component is mixed with the above-mentioned polyfunctional (meth)acrylate monomer, they can be co-crosslinked and further increase the hardness of the formed polymer film.

In formula (A1), R ¹⁰¹ represents a substituted or unsubstituted alkyl group. Alkyl includes methyl, ethyl, propyl, isopropyl, hexyl, decyl, hexadecyl. The alkyl group preferably has 1-30 carbon atoms, more preferably 1-16 carbon atoms, even more preferably 1-6 carbon atoms.

X represents a hydroxyl group or a hydrolyzable group. Hydrolyzable groups include, for example, alkoxy groups (preferably those having 1 to 5 carbon atoms, for example, methoxy, ethoxy), halogen atoms (for example, Cl, Br, I), and R ² COO ( Wherein R ² is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; examples thereof are CH ₃ COO, C ₂ H ₅ COO). Preferably, it is alkoxy, more preferably methoxy or ethoxy.

m represents an integer of 1-3, and is preferably 1 or 2, more preferably 1.

If there are multiple R ¹⁰¹ or X in the compound, they may be the same or different.

Among the organosilane compounds of formula (A1), organosilane compounds of formula (B) having vinyl-polymeric substituents are preferred.

Specific examples of the compound of formula (A1) include (M-1) to (M-10) described above in this specification.

The organosilane compound preferably used in the fourth embodiment of the present invention is an organosilyl compound of the following formula (A2):

R _m Si(X) _n

Wherein X represents -OH, a halogen atom, -OR ¹⁰² or -OCOR ¹⁰² ; R and R ¹⁰² each represent a substituted or unsubstituted alkyl group with 1-10 carbon atoms; m+n=4, and m and n are respectively Represents an integer of 0 or greater.

The compound of formula (A2) forms the matrix according to the sol-gel method of hydrolysis combined with mutual condensation. In the present invention, the compound of formula (A2) includes the compound of following four formulas:

(a) Si(X) ₄

(b) RSi(X) ₃

(c)R ₂ Si(X) ₂

(d)R ₃ Si(X)

Component (a) is specifically described. Specific examples of the compound include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetra-n-propoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-tert-butoxysilane base silane. Particular preference is given to tetramethoxysilane and tetraethoxysilane.

Component (b) is described. In component (b), R is a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms. For example, it includes alkyl groups such as methyl, ethyl, n-propyl, isopropyl; and γ-chloropropyl, vinyl, CF ₃ CH ₂ CH ₂ CH ₂ -, C ₂ F ₅ CH ₂ CH ₂ CH ₂ -, C ₃ F ₇ CH ₂ CH ₂ CH ₂ -, C ₂ F ₅ CH ₂ CH ₂ -, CF ₃ OCH ₂ CH ₂ CH ₂ -, C ₂ F ₅ OCH ₂ CH ₂ CH ₂ -, C ₃ F ₇ OCH ₂ CH ₂ CH ₂ -, (CF ₃ ) ₂ CHOCH ₂ CH ₂ CH ₂ -, C ₄ F ₉ CH ₂ OCH ₂ CH ₂ CH ₂ -, 3-(perfluorocyclohexyloxy)propyl, H (CF ₂ ) ₄ CH ₂ OCH ₂ CH ₂ CH ₂ -, H(CF ₂ ) ₄ CH ₂ CH ₂ CH ₂ -, 3-glycidyloxypropyl, 3-acryloyloxypropyl, 3-methyl Acryloyloxypropyl, 3-mercaptopropyl, phenyl, 3,4-epoxycyclohexylethyl. X in the organosilane is -OH, a halogen atom, or preferably an alkoxy group having 1 to 5 carbon atoms, or an acyloxy group having 1 to 4 carbon atoms. For example, it includes chlorine atom, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy and acetoxy.

Specific examples of component (b) are methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyl Triethoxysilane, Isopropyltrimethoxysilane, Isopropyltriethoxysilane, 3-Chloropropyltrimethoxysilane, 3-Chloropropyltriethoxysilane, Vinyltrimethoxysilane , Vinyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3 -Acryloxypropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane Oxysilane, 3-mercaptopropyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3,4-epoxycyclohexylethyltrimethoxysilane, 3,4- Epoxycyclohexylethyltriethoxysilane, CF ₃ CH ₂ CH ₂ CH ₂ Si(OCH ₃ ) ₃ , C ₂ F ₅ CH ₂ CH ₂ CH ₂ Si(OCH ₃ ) ₃ , C ₃ F ₇ CH ₂ CH ₂ CH ₂ Si(OCH ₃ ) ₃ , C ₂ F ₅ OCH ₂ CH ₂ CH ₂ Si(OCH ₃ ) ₃ , C ₃ F ₇ OCH ₂ CH ₂ CH ₂ Si(OC ₂ H ₅ ) ₃ , (CF ₃ ) ₂ CHOCH ₂ CH ₂ CH ₂ Si(OCH ₃ ) ₃ , C ₄ F ₉ CH ₂ OCH ₂ CH ₂ CH ₂ Si(OCH ₃ ) ₃ , H(CF ₂ ) ₄ CH ₂ OCH ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , 3-(perfluorocyclohexyloxy)propylsilane.

Among them, organosilanes having fluorine atoms are preferable. When R is an organosilane having no fluorine atoms, methyltrimethoxysilane or methyltriethoxysilane is preferred. One or more different types of the aforementioned organosilanes may be used in the present invention alone or in combination.

Component (c) is described. Component (c) is an organosilane represented by R ₂ Si(X) ₂ (where R has the same meaning as in the organosilane of component (b) above). The two Rs may be different substituents. In the composition of the present invention, the component is hydrolyzed and condensed to obtain a hydrolyzate or a partial condensate or a mixture thereof, which is used as a binder in the composition, and softens the coating film and improves the alkali resistance of the film.

Specific examples of these organosilanes are dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, di-n-propyldimethylsilane Oxysilane, di-n-propyldiethoxysilane, di-isopropyldimethoxysilane, di-isopropyldiethoxysilane, diphenyldimethoxysilane, diphenyldimethoxysilane Ethoxysilane, (CF ₃ CH ₂ CH ₂ ) ₂ Si(OCH ₃ ) ₂ , (CF ₃ CH ₂ CH ₂ CH ₂ ) ₂ Si(OCH ₃ ) ₂ , (C ₃ F ₇ OCH ₂ CH ₂ CH ₂ ) ₂ Si(OCH ₃ ) ₂ , [H(CF ₂ ) ₆ CH ₂ OCH ₂ CH ₂ CH ₂ ] ₂ Si(OCH ₃ ) ₂ , (C ₂ F ₅ CH ₂ CH ₂ ) ₂ Si(OCH ₃ ) ₂ . Organosilanes containing fluorine atoms are preferred. When R is an organosilane having no fluorine atoms, dimethyldimethoxysilane and dimethyldiethoxysilane are preferred. One or more different types of organosilanes of component (c) may be used in the present invention alone or in combination.

Component (d) is described. Component (d) is an organosilane represented by the formula R ₃ Si(X) (wherein R has the same meaning as in the organosilane of component (b) above). The three R's may be different substituents. In the composition of the present invention, this component serves to make the coating film hydrophobic and to improve the alkali resistance of the coating film.

Specific examples of triorganosilanes include trimethylmethoxysilane, trimethylethoxysilane, triethylmethoxysilane, triethylethoxysilane, tri-n-propylmethoxysilane, tri- n-propylethoxysilane, tri-isopropylmethoxysilane, tri-isopropylethoxysilane, triphenylmethoxysilane, triphenylethoxysilane.

In the present invention, the proportions of components (a) to (d) are as follows: taking component (a) as the standard, the proportion of component (b) is 0-150% by weight, preferably 5-100% by weight, more preferably 10-60% by weight. Based on component (a), the proportion of component (c) is 0-100% by weight, preferably 1-60% by weight, more preferably 1-40% by weight. Based on the component (a), the proportion of the component (d) is 0-10% by weight, preferably 0.1-5% by weight, more preferably 0.5-3% by weight. Among the components (a)-(d), when the proportion of the component (a) is less than 30% by weight, the adhesiveness and curability of the coating film may decrease.

<solvent>

The solvent for the coating composition for forming the low refractive index layer of the present invention may be any solvent that satisfies the following requirements: it can dissolve or disperse the constituent components, and it can easily form a uniform Flat profile, it ensures the storability of the liquid, and it has a suitable saturated vapor pressure. From these viewpoints, different solvents can be selected for use in the composition.

Specifically, when forming a low-refractive index layer directly on an antiglare hard coat layer, as shown in FIG. 3, it is desirable to use a coating liquid containing a low-boiling solvent having a boiling point not higher than 100°C. The coating liquid may contain a high boiling point solvent, but the amount of the low boiling point solvent is far greater than the amount of the high boiling point solvent. In particular, a coating liquid containing only a low-boiling solvent or a coating liquid containing a large amount of a low-boiling solvent and a very small amount of a high-boiling solvent can give a coating film with better antireflection properties than any other coating film. This is because, when the coating liquid is applied to the rough surface of the anti-glare hard coat by a wet coating method, and then the resulting coating is dried to remove the solvent and lose its fluidity, the coating liquid protrudes from the rough surface. Flows into the recesses, thereby preventing uneven coating to some extent. Solvents with a boiling point not higher than 100°C include, for example, hydrocarbons such as hexane (boiling point 68.7°C), heptane (98.4°C), cyclohexane (80.7°C), benzene (80.1°C); halogenated hydrocarbons such as di Chloromethane (39.8°C), chloroform (61.2°C), carbon tetrachloride (76.8°C), 1,2-dichloroethane (83.4°C), trichloroethylene (87.2°C); ethers such as ether (34.6°C ), diisopropyl ether (68.5°C), propyl ether (90.5°C), tetrahydrofuran (66°C); esters such as ethyl formate (54.2°C), methyl acetate (57.8°C), ethyl acetate (77.1°C) , isopropyl acetate (89°C); ketones such as acetone (56.1°C), 2-butanone (=methyl ethyl ketone, 79.6°C); alcohols such as methanol (64.5°C), ethanol (78.3°C), 2-propanol (82.4°C), 1-propanol (97.8°C); cyano compounds such as acetonitrile (81.6°C), propionitrile (97.4°C); and carbon disulfide (46.2°C). Among them, ketones and esters are preferred; ketones are more preferred. Among ketones, 2-butanone is particularly preferred.

Solvents having a boiling point of 100°C or higher include, for example, octane (125.7°C), toluene (110.6°C), xylene (138°C), tetrachloroethylene (121.2°C), chlorobenzene (131.7°C), di- Alkane (101.3°C), dibutyl ether (142.4°C), isobutyl acetate (118°C), cyclohexanone (155.7°C), 2-methyl-4-pentanone (=MIBK, 115.9°C), 1- Butanol (117.7°C), dimethyl sulfoxide (189°C). Preference is given to cyclohexanone and 2-methyl-4-pentanone.

<Other substances in the low refractive index layer>

In addition to the above materials, the low refractive index layer of the present invention may contain a small amount of a curing agent selected from the group consisting of: more Functional epoxy compounds, polyfunctional isocyanate compounds, aminoplasts, polyacids and their anhydrides. When a curing agent is added, its amount is preferably at most 30 wt%, more preferably at most 20 wt%, even more preferably at most 10 wt%, of the total solid content of the low-refractive index layer film.

In order to impart dustproof and antistatic properties to the layer, dustproof or antistatic agents such as known cationic surfactants or polyoxyalkylene compounds may also be added to the layer. Dustproof and antistatic properties may be part of the functions of the above-mentioned structural units of the polysiloxane compound and the fluorine-containing compound. When dustproofing agents and antistatic agents are added to the layer, the amount thereof is preferably 0.01-20% by weight, more preferably 0.05-10% by weight, particularly preferably 0.1-5% by weight, based on the total solid content of the low-refractive index layer. Examples of preferable compounds of this agent are Dai-Nippon Ink's Megafac F-150 (trade name) and Toray-Dow Coming's SH-3748 (trade name), but they are not limited.

The low refractive index layer may contain microvoids. For details, see the specifications in JP-A-9-222502, 9-288201, and 11-6902.

Organic fine particles are also useful in the present invention. For this, see, for example, compounds described in paragraphs [0020] to [0038] of JP-A 11-3820. Their forms may be the same as those of the above-mentioned inorganic fine particles.

Preferably, the thickness of the low refractive index layer is 20-300 nm, more preferably 40-200 nm.

Preferably, the surface energy of the low-refractive index layer of the antireflection film of the fourth embodiment of the present invention is at most 26 mN/m, more preferably 15-25.8 mN/m. Considering the stain resistance of the film, it is preferable that the surface energy of the layer falls within this range, and the low refractive index layer of the antireflection film of the fourth aspect of the present invention means that it is thermosetting or ionizing radiation-containing fluorine compound Properties of fluorocured resin films that can cure cross-linked fluorochemicals. Specifically, when the amount of the fluorine-containing compound in the outermost low-refractive index layer is at most 50% by weight of the total weight of the outermost layer, the entire film surface is uniform and stable.

The surface energy of a solid can be obtained according to the contact angle method, wet heat method and adsorption method, such as Basis and Application of Wetting (published by Realize, December 10, 1989). Preferably the contact angle method is used for the films of the invention. Specifically, two different solutions each having a known surface energy were applied to a protective film of a polarizer to obtain drops thereof thereon. At the intersection of the droplet surface and the film surface, the angle between the tangent of the droplet and the film surface and containing the droplet is defined as the contact angle between the droplet and the film surface. From the contact angle thus defined, the surface energy of the film can be calculated.

Preferably, the contact angle of water with the outermost surface is at least 90°, more preferably at least 95°, even more preferably at least 100°.

It is also preferred that the kinetic friction coefficient of the surface of the low-refractive index layer is at most 0.25, more preferably 0.03-0.20, particularly preferably 0.03-0.15. The coefficient of dynamic friction mentioned in the present invention is between the surface of the low-refractive index layer and a stainless steel ball with a diameter of 5mm, the coefficient of dynamic friction when the stainless steel ball moves at a speed of 60cm/min on the surface of the layer under a load of 0.98N .

Preferably, according to the pencil hardness test in JIS K5400, the hardness of the low refractive index layer is at least H class, more preferably at least 2H class, most preferably at least 3H class.

It is also preferable that the wear of the layer is as small as possible according to the T-bar test in JIS K6902.

(curing method)

The low-refractive-index layer of the antireflection film of the third aspect of the present invention can be formed by as follows: a coating composition is coated on the following layer, then it is dried to remove solvent, and has predetermined temperature atmosphere or It is cured by exposing it to ionizing radiation and/or heat at a predetermined temperature on the surface of the film, preferably in an atmosphere having an oxygen concentration of at most 15% by volume. In the present invention, ionizing radiation may be any ordinary ionizing radiation that causes excitation or ionization when it passes through a substance. It includes particulate rays and electromagnetic waves commonly called radiation. Specifically, it includes alpha rays, beta rays, gamma rays, energetic particles, neutrons, electron rays, light rays (UV rays and visible rays). Particularly preferred ionizing radiations for use in the present invention are UV radiation and visible radiation.

During curing, the oxygen concentration may be a maximum of 15% by volume, preferably a maximum of 1% by volume, more preferably a maximum of 0.3% by volume. If the oxygen concentration during curing is greater than 15% by volume, since the film thickness of the low-refractive index layer after removal of the solvent is about 0.1 μm, or that is, the film is particularly thin (in other words, the film surface area per unit volume is large), and since it is indispensable Inorganic fine particles of a hollow structure existing in the low-refractive index layer may contain air, and radical deactivation due to oxygen may be significant, resulting in properties of the cured film such as scratch resistance, specifically mentioned later in this specification Resistance to steel wool abrasion and eraser abrasion can be fatally damaged. For the important purpose of preventing the scratch resistance of the layer from being reduced for these reasons, the coating is cured in the present invention in an atmosphere with an oxygen concentration of at most 15% by volume.

In addition to the low-refractive index layer here, layers optionally present in the antireflection film of each aspect of the present invention are described below.

(First aspect and second embodiment of the present invention) (High (medium)-refractive index layer)

When there is a high refractive index layer in the antireflection film of the present invention, its refractive index is preferably 1.65-2.40, more preferably 1.70-2.20. When the film has a medium refractive index layer, its refractive index is controlled so that it can be between the refractive index of the low refractive index layer and the refractive index of the high refractive index layer. Preferably, the refractive index of the medium refractive index layer is 1.55-1.80. It is also preferred that the haze of the high refractive index layer and the medium refractive index layer is at most 3%.

It is preferable to use a cured product of a composition obtained by dispersing inorganic fine particles having a high refractive index in a monomer, an initiator and, for example, hard Coatings are prepared from organosubstituted silicon compounds as described. The inorganic fine particles are preferably oxides of metals (for example, aluminum, titanium, zirconium, antimony). In view of their refractive index, titanium dioxide fine particles are most preferred. When monomers and initiators are used, the coating is cured by polymerization by exposure to active energy rays or heat, resulting in a medium or high refractive index layer with good scratch resistance and good adhesion . Preferably, the average particle diameter of the inorganic fine particles is 10-100 nm.

The titanium dioxide fine particles are particularly preferably inorganic fine particles containing titanium dioxide as its main component and containing at least one element selected from cobalt, aluminum, and zirconium. The main component mentioned in this specification means that the content (weight%) is the largest among all the constituent components of a granule. In the present invention, the inorganic fine particles containing titanium dioxide as a main component preferably have a refractive index of 1.90-2.80, more preferably 2.10-2.80, even more preferably 2.20-2.80. Also preferably, the weight average particle diameter of the primary particles of the inorganic fine particles containing titanium dioxide as a main component is 1-200 nm, more preferably 1-150 nm, even more preferably 1-100 nm, even more preferably 1-80 nm.

The particle size of the inorganic fine particles can be measured according to the light scattering method or by electron microscopy. Preferably, the specific surface area of the inorganic fine particles is 10-400 m ² /g, more preferably 20-200 m ² /g, most preferably 30-150 m ² /g. Also preferably, the crystal structure of the inorganic fine particles containing titanium dioxide as a main component includes a rutile structure, a mixed rutile/anatase structure, an anatase structure, or an amorphous structure as its main component. More preferably, it includes a rutile structure as its main component. The main component mentioned in this specification means that the content (weight%) is the largest among all the constituent components of a granule.

Containing at least one element selected from Co (cobalt), Al (aluminum) and Zr (zirconium), and containing titanium dioxide as a main component, the inorganic fine particles can delay the photocatalytic activity of titanium dioxide therein, and thus effectively improve the present invention. The weather resistance of the high refractive index layer and the medium refractive index layer. Particularly preferably, the added element is Co (cobalt). Also preferably, two or more different types of additive elements may be mixed in the inorganic fine particles.

<Dispersant>

Inorganic fine particles containing titanium dioxide as its main component can be dispersed into the high-refractive index layer and the medium-refractive index layer of the present invention using a dispersant. Preferably, a dispersant having an anionic group is used to disperse the inorganic fine particles containing titanium dioxide as its main component. As the anionic group, groups containing an acidic proton such as carboxyl group, sulfonic acid group (and sulfo group), phosphoric acid group (and phosphono group), sulfinylamino group, and salts thereof are effectively used. More preferred are carboxyl groups, sulfonic acid groups, phosphoric acid groups and salts thereof; even more preferred are carboxyl and phosphoric acid groups. The number of anionic groups in one dispersant molecule may be at least one. In order to further improve the dispersibility of inorganic fine particles, there may be a plurality of anionic groups in the dispersant. Preferably, there may be on average at least two anionic groups, more preferably at least 5 anionic groups, even more preferably at least 10 anionic groups in the dispersant. A dispersant molecule can contain different types of anionic groups.

Also preferably, the dispersant contains crosslinking or polymerizing functional groups. Cross-linking or polymerizing functional groups include ethylenically unsaturated groups (e.g., (meth)acryloyl, allyl, styryl, vinyloxy), cationic polymerization Groups (eg, epoxy, oxetanyl, vinyloxy), polycondensation-reactive groups (eg, hydrolyzed silyl, N-methylol). Preference is given to functional groups bearing ethylenically unsaturated groups. A dispersant for dispersing inorganic fine particles containing titanium dioxide as its main component into the high refractive index layer of the present invention preferably has an anionic group and a crosslinking or polymerizing functional group, wherein the crosslinking or polymerizing functional group is preferably located at the In side branches. Without particular limitation, a dispersant having an anionic group and a crosslinking or polymerizing functional group, wherein the crosslinking or polymerizing functional group is located at a side branch of the dispersant, preferably has a weight average molecular weight (Mw) of at least 1,000. More preferably, the dispersant has a weight average molecular weight (Mw) of 2,000-1,000,000, particularly preferably 5,000-200,000, even more preferably 10,000-100,000.

The amount of the dispersant used is preferably 1-50% by weight of the inorganic fine particles, more preferably 5-30% by weight, most preferably 5-20% by weight. Therein, two or more different types of dispersants may be used in combination.

<Formation method of high (medium)-refractive index layer>

Inorganic fine particles containing titanium dioxide as its main component are used as the dispersion forming the high-refractive-index layer and the medium-refractive-index layer of the present invention. The inorganic fine particles are dispersed in the dispersion medium in the presence of the above-mentioned dispersant. The dispersion medium is preferably a liquid having a boiling point of 60-170°C. Examples of dispersion media are water, alcohols (for example, methanol, ethanol, isopropanol, butanol, benzyl alcohol), ketones (for example, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone ), esters (for example, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl formate, ethyl formate, propyl formate, butyl formate), aliphatic hydrocarbons (for example, hexane, cyclohexane), halogenated hydrocarbons (e.g., methylene chloride, chloroform, carbon tetrachloride), aromatic hydrocarbons (e.g., benzene, toluene, xylene), amides (e.g., dimethylformamide, di methylacetamide, N-methylpyrrolidone), ethers (for example, diethyl ether, dioxane, tetrahydrofuran), ether alcohols (for example, 1-methoxy-2-propanol). Preferred dispersion media are toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol; more preferred are methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone.

The inorganic fine particles are dispersed with a disperser. Examples of dispersers are sand mills (eg, bead mills with pins), high-speed impeller mills, pebble ball mills, rolling mills, attritors, and colloid mills. Particular preference is given to sand mills and high-speed impeller mills. Particles can be pre-dispersed. Examples of the disperser used for the pre-dispersion treatment are a ball mill, a three-roll mill, a kneader, and an extruder. Preferably, the fine inorganic particles are dispersed in the dispersion medium as finely as possible, and the fine inorganic particles dispersed therein have a weight average particle diameter of 1-200 nm, preferably 5-150 nm, more preferably 10-100 nm, even more preferably 10-80 nm. If finely dispersed to a size of at most 200 nm, the inorganic fine particles can be in the high-refractive index layer and the medium-refractive index layer without reducing the transparency of these two layers.

Preferably, the high-refractive-index layer and the medium-refractive-index layer of the present invention are formed by adding, preferably, a binder precursor (such as , the active energy ray that will be mentioned below can curable multifunctional monomer or multifunctional oligomer) and photopolymerization initiator to prepare the coating composition of high refractive index layer and medium refractive index layer, the coating composition coated on a transparent support, and then cured on the support to form the desired high refractive index by crosslinking or polymerization of active energy ray curable compounds (e.g. layer or medium refractive index layer.

Preferably, the binder of the layers is cross-linked or polymerized with the dispersant simultaneously with or after the coating operation of forming the high-refractive-index layer and the medium-refractive-index layer. The binders in the high and medium refractive index layers thus formed bear anionic groups in dispersants, for example, curable polyfunctional monomers or polyfunctional oligomers by the above-mentioned preferred dispersants and active energy rays crosslinking or polymerization reactions. In addition, the anionic group of the binder in the high-refractive-index layer and the low-refractive-index layer has the function of maintaining the dispersed state of the inorganic fine particles, and its crosslinked or polymerized structure gives the binder film-forming properties, and finally , the binder improves the physical strength, chemical resistance, and weather resistance of the high-refractive-index layer and the medium-refractive-index layer containing inorganic fine particles.

The functional group of the active energy ray-curable polyfunctional monomer or polyfunctional oligomer is preferably a functional group polymerizable by exposure to light, electron rays, or radiation. First, a photopolymerizable functional group is more preferable. The photopolymerizable functional group is, for example, an unsaturated polymerizable functional group such as (meth)acryloyl, vinyl, styryl, and allyl. First, a (meth)acryloyl group is preferred. In this specification, "(meth)acrylate" and "(meth)acryloyl" mean "acrylate or methacrylate" and "acryloyl or methacryloyl", respectively.

Specific examples of photopolymerizable polyfunctional monomers having photopolymerizable functional groups include alkylene glycol (meth)acrylate diesters (such as neopentyl glycol acrylate, 1,6-hexanediol di(meth)acrylic acid ester, propylene glycol di(meth)acrylate); polyoxyalkylene glycol (meth)acrylate diesters (e.g. triethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, polyethylene Diol di(meth)acrylate, polypropylene glycol di(meth)acrylate); polyol (meth)acrylate diesters (e.g. pentaerythritol di(meth)acrylate); ethylene oxide or propylene oxide Adducted (meth)acrylic diesters (e.g. 2,2-bis{4-(acryloyloxy-diethoxy)phenyl}propane, 2,2-bis{4-acryloyloxy-polypropylene oxy)phenyl}propane.

Furthermore, the photopolymerizable polyfunctional monomer is also preferably epoxy (meth)acrylates, urethane (meth)acrylates, and polyester (meth)acrylates.

In particular, esters of polyols and (meth)acrylic acid are preferred. More preferred is a polyfunctional monomer having at least 3 (meth)acryloyl groups in one molecule. Specifically, they are trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, 1,2,4-cyclohexane tetra(meth)acrylate, Glycerin triacrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate base) acrylate, tripentaerythritol triacrylate and tripentaerythritol hexaacrylate.

Two or more different types of polyfunctional monomers may be mixed for use in the present invention. Preferably, a photopolymerization initiator is used for polymerization of the photopolymerizable polyfunctional monomer. The photopolymerization initiator is preferably a photo-radical polymerization initiator and a photo-cationic polymerization initiator. A photo-radical polymerization initiator is more preferable. Photo-radical polymerization initiators include, for example, acetophenones, benzophenones, Michler's benzoyl benzoate, α-amyl oxime esters, tetramethylthiuram monosulfide and thioxanthones.

Some photo-radical polymerization initiators are commercially available, and, for example, they are Nippon Kayaku's Kayacure (DETX-S, BS-100, BDMK, CTX, BMS, 2-EAQ, ABQ, CPTX, EPD, ITX, QTX, BTC, MCA), Ciba-Speciality Chemicals' Irgacure (651, 184, 500, 907, 369, 1173, 2959, 4265, 5263), Sartomer's Esacure (KIP100F, KB1, EB3, BP, X33, KTP46, KT47 , KIP150, TZT).

Specifically, a photocleavable photo-radical polymerization initiator is preferably used in the present specification. Photocleavable photo-radical polymerization initiators are described, for example, in the Latest UV Curing Technology (page 159, published by Kazuhiro Takahashi, published by the Technology Information Association, 1991). Some photocurable photo-radical polymerization initiators are commercially available, for example they are Ciba-Speciality Chemicals' Irgacure (651, 184, 907).

Preferably, relative to 100 parts by weight of the polyfunctional monomer, the photopolymerization initiator is used in an amount of 0.1-15 parts by weight, more preferably 1-10 parts by weight. In addition to photopolymerization initiators, photosensitizers can also be used. Specific examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone and thioxanthone. Some photosensitizers are commercially available, for example, they are Nippon Kayaku's Kayacure (DMBI, EPA). Preferably, the photopolymerization reaction is carried out by exposing to ultraviolet rays after the high refractive index layer is formed and dried. The high refractive index layer of the present invention may contain the compound of the above formula (A) and/or its derivative compound.

In order to form the low refractive index layer on the high refractive index layer to constitute the antireflection film of the present invention, the refractive index of the preferred high refractive index layer is 1.55-2.40, more preferably 1.60-2.20, even more preferably 1.65-2.10, most preferably 1.80 -2.00.

In addition to the above components (inorganic fine particles, polymerization initiator, photosensitizer), the high refractive index layer may contain resin, surfactant, antistatic agent, coupling agent, viscosity improver, coloring inhibitor, coloring Agents (pigments, dyes), defoamers, leveling agents, flame retardants, UV absorbers, IR absorbers, tackifiers, polymerization inhibitors, antioxidants, surface modifiers, conductive metal fine particles.

In forming the high refractive index layer, it is preferable to perform the crosslinking reaction or the polymerization reaction of the active energy ray-curable compound in an atmosphere having an oxygen concentration of at most 10% by volume. If formed in an atmosphere having an oxygen concentration of at most 10% by volume, the high-refractive-index layer has the advantage of improved physical strength, chemical resistance, and weather resistance, and in addition, improved adhesion to adjacent layers. More preferably, the crosslinking reaction or polymerization reaction of the active energy ray curable compound forming the layer is at an oxygen concentration of at most 6% by volume, more preferably at most 4% by volume, even more preferably at most 2% by volume, most preferably at most 1% by volume % in an atmosphere.

When the antireflection film is used on a liquid crystal display device, it is also possible to form an undercoat layer in which particles having an average particle diameter of 0.1-10 μm are added, or the particles may be added to a hard coat layer to obtain a light-scattering hard coating. coating to further improve the viewing angle characteristics of the film. The average particle diameter of the particles is preferably 0.2-5.0 μm, more preferably 0.3-4.0 μm, even more preferably 0.5-3.5 μm.

The refractive index of the particles is preferably 1.35-1.80, more preferably 1.40-1.75, even more preferably 1.45-1.75. The particle size distribution of the particles is preferably as narrow as possible. The particle size distribution of the particles can be shown by the S value represented by the following formula, and it is preferably at most 1.5, more preferably at most 1.0, even more preferably at most 0.7.

S＝[D(0.9)-D(0.1)]/D(0.5)

in

D(0.1) refers to 10% of the integral value of volume equivalent particle diameter-corresponding particle diameter;

D(0.5) refers to 50% of the integral value of volume equivalent particle diameter-corresponding particle diameter;

D(0.9) means 90% of the integral value of the volume equivalent particle diameter-corresponding particle diameter.

Preferably, the difference between the refractive index of the particles and the refractive index of the substrate coating is at least 0.02, more preferably 0.03-0.5, particularly preferably 0.05-0.4, even more preferably 0.07-0.3. The particles added to the undercoat layer may be inorganic particles or organic particles as described above for the anti-glare layer in the present invention. Preferably, a base coat is formed between the hard coat layer and the transparent support. Depending on the situation, the base coat can also be used as a hard coat. When the particles with an average particle diameter of 0.1-10 μm are added to the substrate coating, the haze of the substrate coating is preferably 3-60%, more preferably 5-50%, particularly preferably 7-45%, even more preferably 10-40%.

In the antireflection film of the present invention, an inorganic filler is preferably added to the structural layer to increase the film strength. The inorganic fillers incorporated into the structural layers may be the same or different among the layers, and preferably the type and amount of fillers incorporated into the layers vary with desired properties including refractive index, film strength, thickness of the structural layers and coating performance. There is no particular limitation, and the shape of the inorganic filler used in the present invention may be any, including, for example, spherical, flake, fibrous, rod, amorphous or hollow structures. Any of these structures is preferred in the present invention, but spherical fillers are more preferred. This is due to their good dispersibility. The type of inorganic filler is also not particularly limited. However, amorphous fillers are preferred. For example, metal oxides, nitrides, sulfides or halides are preferred; metal oxides are more preferred.

Metal atoms of metal oxides include Na, K, Mg, Ca, Ba, Al, Zn, Fe, Cu, Ti, Sn, In, W, Y, Sb, Mn, Ga, V, Nb, Ta, Ag, Si , B, Bi, Mo, Ce, Cd, Be, Pb and Ni. In order to obtain a transparent cured film, the average particle diameter of the inorganic filler is preferably 0.001-0.2 μm, more preferably 0.001-0.1 μm, even more preferably 0.001-0.06 μm. The average particle size of the particles was determined using a Coulter Counter. In the present invention, the method of using the inorganic filler is not particularly limited. For example, the inorganic filler may be used dry, or may be used after being dispersed in water or an organic solvent. In the present invention, a dispersion stabilizer is preferably used to prevent aggregation and deposition of the inorganic filler. As far as the dispersion stabilizer is concerned, polyvinyl alcohol, polyvinylpyrrolidone, cellulose derivatives, polyamides, phosphates, polyethers, surfactants, silane coupling agents, titanium coupling agents, etc. joint agent. Specifically, a silane coupling agent is preferred because it is effective in increasing the strength of a cured film. The amount of the silane coupling agent used as a dispersion stabilizer is not particularly limited. For example, the amount of the silane coupling agent may be at least 1 part by weight relative to 100 parts by weight of the inorganic filler. The addition method of the dispersion stabilizer is also not particularly limited. For example, the stabilizer may be hydrolyzed in advance and then added to the system, or a silane coupling agent used as a dispersion stabilizer may be mixed with an inorganic filler and then it may be hydrolyzed and condensed. Of these two methods, the latter is preferred. The inorganic filler added to the structural layer will be described below in this specification.

(hard coating]

The hard coat layer of the antireflection film of the present invention is described below.

The hard coat layer includes a binder that imparts hardcoat properties to the layer, optionally a matte particle that imparts anti-glare properties, and a layer that imparts a high refractive index, prevents the layer from shrinking after crosslinking, and increases Inorganic fillers for the mechanical strength of the layer. The binder is preferably a polymer having a saturated hydrocarbon chain or a polyether chain as its main chain structure, more preferably a polymer having a saturated hydrocarbon chain as its main chain structure. It is also preferred that the binder polymer has a crosslinked structure. The binder polymer having a saturated hydrocarbon chain as its main chain structure is preferably a polymer of an ethylenically unsaturated monomer. The binder polymer having a saturated hydrocarbon chain as its main chain structure and having a crosslinked structure is preferably a (co)polymer of monomers containing at least two kinds of ethylenically unsaturated groups. In order to form a high refractive index layer, it is preferable that the monomer structure of the polymer contains an aromatic ring, and at least one atom selected from a halogen atom other than fluorine, and a sulfur atom, a phosphorus atom, and a nitrogen atom.

Monomers containing at least two ethylenically unsaturated groups include polyols and esters of (meth)acrylic acid (e.g., ethylene glycol di(meth)acrylate, 1,4-cyclohexane diacrylate, pentaerythritol Tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate ) acrylate, dipentaerythritol penta(meth)acrylate, pentaerythritol hexa(meth)acrylate, 1,3,5-cyclohexanetriol triacrylate, polyurethane polyacrylate, polyester polyacrylate), vinyl Benzene and its derivatives (e.g., 1,4-divinylbenzene, 2-acryloylethyl 4-vinylbenzoate, 1,4-divinylcyclohexanone), vinyl sulfones (e.g., divinylsulfone), acrylamides (eg, methylenebisacrylamide), and methacrylamides.

Specific examples of high refractive index monomers include bis(4-methacryloylphenylthio)sulfide, vinylnaphthalene, vinylphenylsulfide, 4-methacryloyloxyphenyl-4'-methyl Oxyphenyl sulfide.

The polymerization of the ethylenically unsaturated group-containing monomer can be carried out by exposure to active energy rays or heat in the presence of a photoradical polymerization initiator or a thermal radical polymerization initiator.

Therefore, a coating solution containing a monomer having an ethylenically unsaturated group, a photoradical initiator or a thermal radical initiator, matte particles, and an inorganic filler is prepared and applied to a transparent support, It is then polymerized and cured by exposure to active energy rays and heat to form an antireflective film.

The polymer having a polyether structure as its main chain structure is preferably a ring-opening polymer of a polyfunctional epoxy compound. Ring-opening polymerization of polyfunctional epoxy compounds can be carried out by exposure to active energy rays or heat in the presence of optical or thermal acid generators. Therefore, a coating solution containing a polyfunctional epoxy compound, an optical acid generator or a thermal acid generator, matte particles, and an inorganic filler is prepared, and coated on a transparent support, and then exposed to an active energy ray or Polymerizes and cures under heat to form an antireflective film.

Instead of, or in addition to, monomers with at least two ethylenically unsaturated groups, monomers with crosslinking functional groups can be used to introduce crosslinking functional groups into the polymer and to crosslink The linking functional group reaction thus introduces a crosslinking structure into the binder polymer. Examples of the crosslinking functional group include isocyanate group, epoxy group, aziridinyl group, oxazoline group, aldehyde group, carbonyl group, hydrazine group, carboxyl group, hydroxymethyl group and active methylene group. Vinylsulfonic acids, anhydrides, cyanoacrylate derivatives, melamines, etherified methylols, esters and urethanes, and metal alkoxides such as tetramethoxysilane can also be used as A monomer that introduces a crosslinked structure into a polymer. It is also possible to use functional groups which can crosslink after a decomposition reaction, for example blocked isocyanate groups. Therefore, in the present invention, the cross-linking functional group is not a group that can react directly, but a group that becomes reactive after decomposing. After coating on the support, the binder polymer with such cross-linking functional groups can be coated and heated to form the desired cross-linking structure.

The hard coat layer may optionally contain matte particles, for example, inorganic compound particles or resin particles having an average particle diameter of 1-10 μm, preferably 1.5-7.0 μm. Specific examples of matte particles are inorganic compound particles such as silica particles, TiO ₂ particles; and resin particles such as crosslinked acrylic particles, crosslinked styrene particles, melamine resin particles, benzoguanamine resin particles. Among them, crosslinked styrene particles are more preferred. Matte particles may be true spherical or amorphous in view of their shape. Two or more different types of mat particles may be mixed for use in the present invention. The amount of matte particles that can be used in the anti-glare hard coat layer formed in the present invention is preferably 10-1,000 mg/m ² , more preferably 30-100 mg/m ² . In a particularly preferred embodiment of the hardcoat layer, crosslinked styrene particles are used as matt particles, and large crosslinked styrene particles with a particle size greater than 1/2 the thickness of the hardcoat layer account for all crosslinked styrene particles in the layer. 40-100% of distyryl particles. Here, the particle size distribution of the matte particles is measured according to the Coulter Counter method, and the distribution thus measured is converted into a particle number distribution.

In addition to the above-mentioned matte particles, the hard coat layer preferably contains inorganic fillers to further increase the refractive index of the layer. The inorganic filler includes oxides of at least one metal selected from titanium, zirconium, aluminum, indium, zinc, tin and antimony, and has an average particle size of 0.001-0.2 μm, preferably 0.001-0.1 μm, more preferably 0.001-0.06 μm. Specific examples of inorganic fillers that can be used in the hard coat layer are TiO ₂ , ZrO ₂ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , Sb ₂ O ₃ , ITO. In view of their ability to increase the refractive index of the layer, TiO ₂ and ZrO ₂ are particularly preferred. Preferably, the inorganic filler is surface-treated with a silane coupling agent or a titanium coupling agent. For this treatment, it is preferable to use a surface treatment agent that can provide the surface of the filler with a functional group capable of reacting with the binder. The amount of the inorganic filler added to the layer is preferably 10-90%, more preferably 20-80%, even more preferably 30-75% of the total weight of the hard coat layer. Since the particle size of the filler is much smaller than the wavelength of light, the filler does not cause light scattering around it, and the dispersion formed by dispersing the filler into the binder polymer functions as an optically uniform substance as a whole.

The total refractive index of the mixture of binder and inorganic filler in the hard coat layer of the present invention is preferably 1.57-2.00, more preferably 1.60-1.80.

In order to control the refractive index so as to fall within the above range, the types of the binder and the inorganic filler and the mixing ratio of the two can be appropriately selected and determined. This selection and determination can be easily performed by previous experiments.

Preferably, the thickness of the hard coat layer is 1-10 μm, more preferably 1.2-6 μm.

By so configuring, the antireflective film of the present invention has a haze value of 3-20%, preferably 4-15%, and its average reflectance at 450-650 nm can be at most 1.8%, preferably at most 1.5%. When the haze value and the average reflectance each fall within the above ranges, the antireflection film of the present invention achieves good antiglare and antireflection properties without degrading the quality of a transmitted image.

(Third Embodiment of the Invention) (Light Scattering Layer)

The purpose of forming the light-scattering layer is to impart light-diffusing properties to the film due to at least arbitrary surface light scattering or internal light scattering, and to impart hard-coat properties to improve the scratch resistance of the film. Therefore, it is preferable that the light-scattering layer contains a translucent resin for imparting a hard film property to the film and translucent particles for imparting a light-scattering property, and may optionally contain a resin that imparts a high refractive index to the layer and prevents the layer from shrinking and increasing after crosslinking. Inorganic fillers for the mechanical strength of the layer.

In order to impart hard-coat properties to the film, the thickness of the light-scattering layer is preferably 1-10 μm, more preferably 2-6 μm. When the thickness thereof falls within the above range, the layer can satisfactorily impart hard-coat properties to the film, and its processability is not impaired, for example, not rolled up or brittle.

The translucent resin is preferably the binder polymer described above in the specification, in the paragraph "Hard coat layer" in the first and second embodiments of the present invention.

Translucent particles in the light scattering layer are used to impart anti-glare properties to this layer. The particles may have an average particle size of 0.5-5 μm, preferably 1.0-4.0 μm. If the average particle diameter thereof is less than 0.5 μm, the light scattering angle distribution may widen to an obtuse angle, and the letter resolution of the display may be lowered, and the surface roughness of the layer may be difficult to form. As a result, the anti-glare performance of the light-scattering layer may be insufficient, and thus this layer is not satisfactory. On the other hand, if the average particle diameter is larger than 5 μm, it is necessary to increase the thickness of the light scattering layer, and this will cause some problems since the layer will be rolled up very much and the material cost will increase.

Specific examples of translucent particles include inorganic compound particles such as silica particles, _TiO particles; and resin particles such as acrylic particles, cross-linked acrylic particles, methacrylic particles, cross-linked methacrylic particles, polystyrene particles, cross-linked Distyryl granules, melamine resin granules, benzoguanamine resin granules. Among them, crosslinked styrene particles, crosslinked acrylic particles, crosslinked acrylstyrene particles, and silica particles are more preferable.

Considering their shape, the translucent particles may be spherical or amorphous.

Two or more different types of translucent particles may be mixed for use in the present invention. Translucent particles with larger particle sizes can impart anti-glare properties to the light scattering layer, while particles with smaller particle sizes can impart different optical properties to the layer. For example, when an antireflection film is adhered to a high-definition display of 133 ppi or more, it is required that the display has no optical problems such as glare mentioned above in this specification. Glare is caused by pixel expansion or reduction due to the surface roughness of the film (surface roughness is beneficial to the anti-glare properties of the film), thereby losing the brightness uniformity of the film. When translucent particles having a smaller particle size than the particles imparting anti-glare properties to the film and having a different refractive index from the binder are mixed with large-diameter translucent particles, the anti-glare properties of the film can be significantly improved.

The translucent particles are most preferably monodisperse in consideration of their particle size distribution, and more preferably particles whose particle sizes are as close to each other as possible. For example, when particles having a particle diameter at least 20% larger than their average particle diameter are defined as coarse particles, the proportion of coarse particles is preferably at most 1% of the total number of translucent particles, more preferably at most 0.1%, even more preferably at most 0.01%. Translucent particles having such a particle size distribution can be obtained by classification after the production reaction thereof, and when the frequency of classification increases, the particles can have a more preferable particle size distribution.

Considering the light-scattering effect of the light-scattering layer, image resolution, surface whitening and surface glare, the translucent particles can be preferably 3-30% by weight, more preferably 5-20% by weight, of the total solids content of the light-scattering layer The amount added to the light scattering layer.

Preferably, the density of the translucent particles is 10-1000 mg/m ³ , more preferably 100-700 mg/m ³ .

The particle size distribution of the translucent particles can be measured according to the Coulter Counter method, and the distribution thus determined is converted into a particle number distribution.

In addition to the aforementioned translucent particles, the light-scattering layer preferably contains an inorganic filler to further increase the refractive index of the layer. The inorganic filler comprises an oxide of at least one metal selected from titanium, zirconium, aluminum, indium, zinc, tin and antimony, and has an average particle size of at most 0.2 μm, preferably at most 0.1 m, more preferably at most 0.06 μm.

On the contrary, in the light scattering layer including high refractive index translucent particles, in order to increase the refractive index difference with the translucent particles, it is also preferable to use silicon oxide to lower the refractive index of the light scattering layer. The preferred particle size of the silica particles is the same as that of the above-mentioned inorganic filler.

Specific examples of inorganic fillers that can be used for the light scattering layer are TiO ₂ , ZrO ₂ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , Sb ₂ O ₃ , ITO, SiO ₂ . In view of their ability to increase the refractive index of the layer, TiO ₂ and ZrO ₂ are particularly preferred. Preferably, the inorganic filler is surface-treated with a silane coupling agent or a titanium coupling agent. For this treatment, it is preferable to use a surface treatment agent that can impart a functional group capable of reacting with the binder to the surface of the filler.

When an inorganic filler is used, its amount added to the light scattering layer is preferably 10-90%, more preferably 20-80%, even more preferably 30-75% of the total weight of the light scattering layer.

Since the particle diameter of the filler is much smaller than the wavelength of light, the filler does not cause light scattering around it, and the dispersion formed by dispersing the filler into the binder polymer functions as an optically uniform substance as a whole.

The light-scattering layer may also contain at least any of the above-mentioned organosilane compound and its sol component.

The amount of the sol component that can be added to layers other than the low-refractive index layer is preferably 0.001 to 50% by weight, more preferably 0.01 to 20% by weight, and even more preferably 0.05% to the total solids content of the layer to which the component is added. - 10% by weight, even more preferably 0.1-5% by weight. The restriction on the amount of the organosilane compound or its sol component added to the light-scattering layer is less severe than that of the low-refractive index layer. Therefore, organosilane compounds are preferably used in the light scattering layer.

The total refractive index of the mixture of translucent resin and translucent particles of the present invention is preferably 1.48-2.00, more preferably 1.50-1.80. In order to control the refractive index to fall within the above range, the types of translucent resin and translucent particles and the mixing ratio of the two can be appropriately determined and selected. And this selection and determination can be easily performed by previous experiments.

In the present invention, the difference in refractive index between the translucent resin and the translucent particles (refractive index of the translucent particles−refractive index of the translucent resin) is preferably 0.02-0.2, more preferably 0.05-0.15. When the difference falls within this range, the internal scattering effect of the layer is sufficient, and the layer has no glare, and the film surface does not have haze.

Preferably, the refractive index of the translucent resin is 1.45-2.00, more preferably 1.48-1.70.

Also preferably, the translucent particles have a refractive index of 1.40-1.80, more preferably 1.45-1.70.

The refractive index of the translucent resin can be measured directly using Abbe's refractometer, or can be quantitatively determined by reflectance spectroscopy or spectroscopic ellipsometry.

In order that the light-scattering layer formed can have good surface uniformity without coating problems such as coating unevenness, drying unevenness, and point defects, the coating composition of the light-scattering layer of the present invention contains a fluorine-containing surfactant or Silicone-type surfactants either contain both. Specifically, since the fluorine-containing surfactant is more effective in preventing surface defects of the antireflection film of the present invention, such as its coating unevenness, drying unevenness, and point defects, even when it is added to the layer in a large amount Hours are also effective, so fluorosurfactants are preferred.

The surfactant is used to improve the surface uniformity of the formed layer and to improve the rapid coating performance of the coating composition, thereby increasing the producibility of the antireflection film.

A preferable example of the fluorine-containing surfactant is a fluorine-aliphatic group-containing copolymer (which will be abbreviated as "fluoropolymer" hereinafter in this specification). Useful examples of fluoropolymers are acrylic resins and methacrylic resins containing repeating units corresponding to the following monomers (i) and repeating units corresponding to the following monomers (ii), and they and ethylene which can be copolymerized with them monomeric copolymers.

(i) Fluoro-aliphatic group-containing monomers of the following formula (3):

In formula (3), R ¹¹ represents a hydrogen atom or a methyl group; X represents an oxygen atom, a sulfur atom or -N(R ¹² )-. R ¹² represents a hydrogen atom or an alkyl group having 1-4 carbon atoms, specifically a methyl, ethyl, propyl or butyl group, preferably a hydrogen atom or a methyl group. X is preferably an oxygen atom.

In formula (3), m is preferably an integer of 1-6, more preferably 2.

In formula (3), n is 1-3. Mixtures of monomers in which n is 1-3 may also be used in the present invention.

(ii) a monomer of the following formula (4) that can be copolymerized with the above (i):

In formula (4), R ¹³ represents a hydrogen atom or a methyl group, and Y represents an oxygen atom, a sulfur atom or -N(R ¹⁵ )-. R ¹⁵ represents a hydrogen atom or an alkyl group having 1-4 carbon atoms, specifically a methyl, ethyl, propyl or butyl group, preferably a hydrogen atom or a methyl group. Y is preferably an oxygen atom, -N(H)- or -N(CH ₃ )-.

R ¹⁴ represents an optionally substituted, linear, branched or cyclic alkyl group having 4-20 carbon atoms. The substituents of the alkyl group of ^R14 include hydroxyl, alkylcarbonyl, arylcarbonyl, carboxyl, alkyl ether, aryl ether, halogen atom (such as fluorine, chlorine or bromine), nitro, cyano and amino. However, the substituent is not limited thereto. Preferred examples of linear, branched or cyclic alkyl groups having 4-20 carbon atoms are linear or branched butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, Undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, octadecyl, and eicosyl; monocyclic alkyl groups such as cyclohexyl and cycloheptyl; and polycyclic Alkyl groups are, for example, bicycloheptyl, bicyclodecanyl, tricycloundecyl, tetracyclododecyl, adamantyl, norbornyl and tetracyclodecanyl.

The copolymerization ratio of the fluoro-aliphatic group-containing monomer of formula (3) in the fluoropolymer used in the present invention is at least 10 mol% of the total amount of copolymerization of all constituent monomers of the fluoropolymer, preferably 15-70 mol%, more preferably 20-60 mol%.

Preferably, the weight average molecular weight of the fluoropolymer used in the light scattering layer is 3,000-100,000, more preferably 5,000-80,000.

The preferred amount of the fluoropolymer in the light-scattering layer is 0.001-5% by weight, more preferably 0.005-3% by weight, even more preferably 0.01-1% by weight of the coating liquid for forming the light-scattering layer. Falling within this range, the fluoropolymer is sufficiently effective that the coating dries without any problems, and furthermore, the fluoropolymer does not have any negative impact on film properties (eg, reflectivity, scratch resistance).

The following relates to examples of specific structures of fluoropolymers used in the present invention, however, the present invention is not limited thereto. The numbers after each molecular formula represent the mole fraction of monomer components. Mw refers to the weight average molecular weight of the polymer.

However, when the above-mentioned fluoropolymer is used for the light-scattering layer, the surface energy of the light-scattering layer decreases due to segregation of functional groups containing F atoms on the surface of the layer. When on the layer, the problem of degradation of the anti-reflection performance of the film will occur. This is because the wettability of the curable composition forming the low-refractive index layer would decrease, with the result that the formed low-refractive index layer would have fine surface unevenness undetectable to the naked eye and its surface uniformity would thus decrease. In order to solve this problem, the present inventors have found that, in particular, by controlling the structure of the fluoropolymer used in the layer and its amount, thereby controlling the surface energy of the light-scattering layer to preferably fall within 20mN·m ⁻¹ -50mN·m ^{−1 1} , more preferably 30mN·m ^-1 to 40mN·m ^-1 is effective. In order to obtain the above surface energy level, the ratio of peaks derived from fluorine atoms to peaks derived from carbon atoms measured by X-ray photoelectron spectrometry, F/C, must fall within 0.1-1.5.

In addition to the above, different methods can be used. Specifically, when forming the upper layer, a fluoropolymer capable of being extracted from the solvent forming the upper layer is selected to prevent polymer segregation at the surface of the lower layer (=interface of the upper layer and the lower layer) and to ensure adhesion between the upper layer and the lower layer. Compatibility. As a result, even in high-speed coating, the formed antireflection film will have flat surface uniformity and good scratch resistance. According to another method of preventing a decrease in surface free energy, before forming a low-refractive index layer thereon, the surface energy of the light-scattering layer can be controlled to fall within the above range, and the desired object can also be achieved.

Examples of the fluoropolymer that can be extracted from the solvent used to form the upper layer are a homopolymer of a monomer of the following formula (5), and a copolymer of a monomer of the formula (5) and a monomer of the following formula (6) things.

(i) Fluoro-aliphatic group-containing monomers of the following formula (5):

In formula (5), R ¹⁶ represents a hydrogen atom, a halogen atom or a methyl group, and preferably a hydrogen atom or a methyl group. X represents an oxygen atom, a sulfur atom or -N(R ¹⁷ )-, preferably an oxygen atom or -N(R ¹⁷ )-, more preferably an oxygen atom. R ¹⁷ represents a hydrogen atom or an optionally substituted alkyl group having 1-8 carbon atoms, and preferably a hydrogen atom or an alkyl group having 1-4 carbon atoms, more preferably a hydrogen atom or a methyl group. X is preferably an oxygen atom.

In formula (5), m represents an integer of 1-6, and preferably an integer of 1-3, more preferably 1.

In formula (5), n represents an integer of 1-18, and preferably an integer of 4-12, more preferably an integer of 6-8.

The fluoropolymer may contain two or more different types of fluoro-aliphatic group-containing monomers of formula (5) as its constituents.

(ii) monomers of the following formula (6) that can be copolymerized with the above (i):

In formula (6), R ¹⁸ represents a hydrogen atom, a halogen atom or a methyl group, preferably a hydrogen atom or a methyl group. Y represents an oxygen atom, a sulfur atom or -N(R ²⁰ )-, preferably an oxygen atom or -N(R ²⁰ )-, more preferably an oxygen atom. R ²⁰ represents a hydrogen atom or an alkyl group having 1-8 carbon atoms, preferably a hydrogen atom or an alkyl group having 1-4 carbon atoms, more preferably a hydrogen atom or a methyl group.

R ¹⁹ represents an optionally substituted, linear, branched or cyclic, alkyl group having 1-20 carbon atoms, an alkyl group containing a poly(alkenyloxy) group, or an optionally substituted aromatic group (eg, phenyl or naphthyl). Preferably, it is linear, branched or cyclic, an alkyl group having 1-12 carbon atoms, or an aromatic group having a total of 6-18 carbon atoms, more preferably linear, branched or cyclic , an alkyl group having 1 to 8 carbon atoms.

Specific examples of fluoropolymers are referred to below.

When the low-refractive index layer is coated on the light-scattering layer while preventing the decrease in surface energy, it is possible to prevent the anti-reflection performance of the film from deteriorating. When forming the light-scattering layer, it is preferable to use a fluoropolymer to lower the surface tension of the coating liquid and improve the surface uniformity of the formed light-scattering layer, and it is also preferable to maintain high productivity by using a rapid coating method. After forming the light-scattering layer, the layer is subjected to surface treatment such as corona treatment, UV treatment, heat treatment, saponification treatment or solvent treatment, preferably corona treatment in order to prevent a decrease in surface free energy. Therefore, before forming the low-refractive index layer thereon, the surface energy of the light-scattering layer is controlled within the above range, and thus the desired purpose can be achieved.

The present inventors have confirmed that the intensity distribution of scattered light measured by a goniophotometer is related to the viewing angle improvement effect of a display. Specifically, the viewing angle characteristic is better when light from the backlight is diffused to a higher degree by the light-diffusing film on the viewing-side surface of the polarizing plate. However, if the light is diffused too much, some problems may arise that backscattering may increase and frontal brightness may decrease, or the scattering may be too large and image sharpness may thereby be reduced. Therefore, it is necessary to control the scattered light intensity distribution to fall within a predetermined range. Assuming this situation, the present inventors further researched and found that in order to obtain the desired visibility characteristics, the intensity of scattered light at a light exit angle of 30° in the scattered light map is particularly related to the viewing angle improvement effect of the display, relative to light The intensity of light at an exit angle of 0° is preferably 0.01%-0.2%, more preferably 0.02%-0.15%.

Scattered light spectra can be formed by analyzing light scattering films with an automatic goniophotometer, Model GP-5, of Murakami Color Technology Laboratory.

A thixotropic agent may be added to the coating composition forming the light scattering layer of the present invention. Thixotropic agents include silica and mica with a particle size of up to 0.1 μm. In general, the addition amount of the agent is preferably about 1 to 10 parts by weight relative to 100 parts by weight of the UV-curable resin in the composition.

(high refractive index layer, medium refractive index layer)

The antireflection film of the present invention may include a high refractive index layer and a medium refractive index layer to have better antireflection performance.

The refractive index of the high refractive index layer is 1.55-2.40. As long as the layer configuration of the antireflection film has layers whose refractive index falls within this range, it can be said that the film contains a high refractive index layer. This range of refractive index is generally used for high-refractive index layers and medium-refractive index layers. However, in this specification, these layers are generally referred to as "high refractive index layers".

When the film includes both a high-refractive-index layer and a medium-refractive-index layer, the layer whose refractive index is higher than that of the support, light-scattering layer, and medium-refractive-index layer can be called a high-refractive-index layer, and has a high refractive index Layers above the support and light scattering layer but lower than the high refractive index layer may be referred to as medium refractive index layers. The refractive index can be appropriately controlled according to the types and ratios of inorganic fine particles and binders added.

<Inorganic fine particles containing titanium dioxide as its main component>

The high-refractive-index layer and/or the medium-refractive-index layer contains inorganic fine particles containing titanium dioxide as its main component and containing at least one element selected from cobalt, aluminum, and zirconium. The main component mentioned in the present invention means that its content (% by weight) is the largest among all the constituent components in the granule.

In the present invention, the inorganic fine particles containing titanium dioxide as their main component preferably have a refractive index of 1.90-2.80, most preferably 2.20-2.80. It is also preferred that the weight average particle diameter of the primary particles of the inorganic fine particles is 1-200 nm, more preferably 2-100 nm, even more preferably 2-80 nm.

Since the inorganic fine particles containing titanium dioxide as its main component contain at least one element selected from Co, Al, and Zr, the photocatalytic activity of titanium dioxide in the particles can be delayed, and the particles can improve the weather resistance of the high-refractive index layer .

The inorganic fine particles containing titanium dioxide as its main component used in the present invention may be surface-treated. The surface treatment can be performed by using a cobalt-containing inorganic compound, or an inorganic compound such as Al(OH) ₃ or Zr(OH) ₄ , or an organic compound such as a silane coupling agent. By such surface treatment, the inorganic fine particles containing titanium dioxide as its main component used in the present invention can have a core/shell structure as in JP-A-2001-166104.

Regarding the shape of the inorganic fine particles containing titanium dioxide as its main component located in the high-refractive-index layer and/or the medium-refractive-index layer, the particles are preferably granular, spherical, cubic, spindle-shaped or amorphous, more preferably amorphous or spindle-shaped. shape.

<Dispersant>

Dispersants can be used to disperse inorganic fine particles. Preferably, dispersants bearing anionic groups are used for the dispersion.

As the anionic group, a group having an acidic proton such as carboxyl group, sulfonic acid group (and sulfo group), phosphoric acid group (and phosphono group), sulfinylamino group, and salts thereof are effectively used. More preferred are carboxyl groups, sulfonic acid groups, phosphoric acid groups and salts thereof; even more preferred are carboxyl and phosphoric acid groups. The number of anionic groups in one dispersant molecule may be at least one on average, but preferably at least 2, more preferably at least 5, even more preferably at least 10. A dispersant molecule can contain different types of anionic groups. Also preferably, the dispersant contains crosslinking or polymerizing functional groups.

<High Refractive Index Layer etc. and Formation Method thereof>

As the dispersion forming the high-refractive index layer and/or the medium-refractive index layer of the present invention, inorganic fine particles containing titanium dioxide as its main component are used.

The inorganic fine particles are dispersed in the dispersion medium in the presence of the above-mentioned dispersant.

The dispersion medium is preferably a liquid having a boiling point of 60-170°C. Examples of dispersion media are water, alcohols, ketones, esters, aliphatic hydrocarbons, halogenated hydrocarbons, aromatic hydrocarbons, amides, ethers, ether alcohols. Preference is given to toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol.

The dispersion medium is more preferably methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone.

The inorganic fine particles are dispersed with a disperser. Examples of dispersers are sand mills (eg, bead mills with pins), high-speed impeller mills, pebble ball mills, rolling mills, attritors, and colloid mills. Particular preference is given to sand mills and high-speed impeller mills. Particles can be pre-dispersed. Examples of the disperser used for the pre-dispersion treatment are a ball mill, a three-roll mill, a kneader, and an extruder.

Preferably, the fine inorganic particles are dispersed in the dispersion medium as finely as possible, and the weight average particle diameter of the particles dispersed therein is 1-200 nm, preferably 5-150 nm, more preferably 10-100 nm, even more preferably 10-80 nm.

If finely dispersed to a particle diameter of at most 200 nm, the inorganic fine particles can be in the high refractive index layer without lowering the transparency of the layer.

Preferably, the high-refractive-index layer and/or the medium-refractive-index layer of the present invention are formed as follows: To a dispersion prepared by dispersing inorganic fine particles in a dispersion medium as described above, it is preferable to add a binding agent required for forming a matrix. agent precursor (it may be the same as that in the above-mentioned light scattering layer) and photopolymerization initiator, thereby preparing a coating composition of a high refractive index layer, and coating the coating composition on a transparent support, and then by ionizing Crosslinking or polymerization of radiation-curable compounds (eg, polyfunctional monomers or oligomers) cures the coating composition on the transparent support to form the desired layer.

Preferably, a photopolymerization initiator is used for polymerization of the photopolymerizable polyfunctional monomer. The photopolymerization initiator is preferably a photo-radical polymerization initiator and a photo-cationic polymerization initiator. More preferred is a photo-radical polymerization initiator. As the photo-radical polymerization initiator, the same initiators as used in the above-mentioned antiglare hard coat layer can also be used for the high refractive index layer and/or the medium refractive index layer.

The binder in the high-refractive-index layer and/or the medium-refractive-index layer preferably has silanol groups. Since the binders in these layers also have silanol groups, the physical strength, chemical resistance, and weather resistance of the high-refractive index layer and/or the medium-refractive index layer can be further improved.

Silanol groups can be introduced into the adhesive by adding a compound having a crosslinking or polymerizing functional group to a coating composition for the high refractive index layer, and then coating the coating composition on a transparent support, Crosslinking or polymerizing the dispersant and the polyfunctional monomer or oligomer can thereby introduce silanol groups into the adhesive.

It is also preferred that the binder in the high refractive index layer and/or the medium refractive index layer contains amino or quaternary ammonium groups. Monomers having amino or quaternary ammonium groups are effective in maintaining good dispersion of inorganic fine particles in the high-refractive index layer, and are effective in forming high-refractive-index layers and medium-refractive-index layers with good physical strength, chemical resistance, and weather resistance .

A cross-linked or polymerized binder has a structure in which the main chain of the polymer is cross-linked or polymerized. Examples of the main chain of the polymer are polyolefins (saturated hydrocarbons), polyethers, polyureas, polyurethanes, polyesters, polyamines, polyamides and melamine resins. Preferred are polyolefin backbones, polyether backbones, and polyurea backbones; more preferred are polyolefin backbones and polyether backbones; most preferred are polyolefin backbones.

The binder is preferably a copolymer having repeating units containing anionic groups and repeating units containing crosslinked or polymeric structures. The proportion of repeating units containing anionic groups in the copolymer is preferably 2-96 mol%, more preferably 4-94 mol%, most preferably 6-92 mol%. An anionic group-containing repeating unit may have two or more anionic groups. The proportion of repeating units containing a crosslinked or polymeric structure in the copolymer is preferably 4-98 mol%, more preferably 6-96 mol%, most preferably 8-94 mol%.

In addition to the above-mentioned inorganic fine particles containing titanium dioxide as its main component, the high-refractive index layer and/or the medium-refractive index layer may contain any other inorganic fine particles. Other inorganic fine particles may be the same as in the above-mentioned antiglare hard coat layer. Preferably, these particles are dispersed as finely as possible in the high-refractive index layer and/or the medium-refractive index layer. For the preferred particle size of the dispersed particles and the preferred primary particle size of the particles, see that described in the paragraph of the anti-glare hard coat layer.

The content of the fine inorganic particles in the high refractive index layer is preferably 10 to 90% by weight, more preferably 15 to 80% by weight, even more preferably 15 to 75% by weight relative to the weight of the high refractive index layer. Two or more different types of fine inorganic particles may be mixed for the high refractive index layer.

When the low-refractive-index layer is on the high-refractive-index layer, the high-refractive-index layer preferably has a higher refractive index than the transparent support.

Binders may also be preferred in the high refractive index layer by means of ionizing radiation-curable compounds containing aromatic rings, ionizing radiation-curable compounds containing halogens other than fluorine (e.g., Br, I, Cl) , or ionizing radiation-curable compounds containing atoms S, N or P obtained by crosslinking or polymerization.

In order to form a low-refractive-index layer on the high-refractive-index layer to construct an antireflective film, the high-refractive-index layer preferably has a refractive index of 1.55-2.40, more preferably 1.60-2.20, even more preferably 1.65-2.10, and most preferably 1.80-2.00.

In addition to the above components (inorganic fine particles, polymerization initiator, photosensitizer), the high refractive index layer and/or the medium refractive index layer may contain resin, surfactant, antistatic agent, coupling agent, viscosity improving Agents, coloring inhibitors, colorants (pigments, dyes), anti-glare particles, defoamers, leveling agents, flame retardants, UV absorbers, IR absorbers, tackifiers, polymerization inhibitors, antioxidants, surface modifiers agent, conductive metal fine particles.

The thickness of the high-refractive-index layer and/or the medium-refractive-index layer can be appropriately designed according to their uses. When the high-refractive index layer and/or the medium-refractive index layer are used as the optical interference layer described later in this specification, the layer thickness is preferably 30-100 nm, more preferably 50-170 nm, even more preferably 60-150 nm.

When forming the high refractive index layer and/or the medium refractive index layer, the crosslinking reaction or polymerization reaction of the ionizing radiation-curable compound is preferably at an oxygen concentration of at most 10% by volume, more preferably at most 6% by volume, even more preferably at most 2% by volume %, most preferably in an atmosphere with a maximum of 1% by volume.

<other layers>

Other layers may be placed between the transparent support of the present invention and the light-scattering layer. For example, antistatic layers (when the surface resistivity on the display side has to be reduced, or when there is a problem of dust sticking to the panel surface), hard coatings (when the light scattering layer can be omitted), moisture barriers, adhesion enhancement layer, and an interference fringe prevention layer.

These layers can be formed by any known method.

(the fourth implementation)

The antireflection film of the present invention comprises a cellulose acylate film support having a light-diffusing layer obtained by coating or a high-refractive-index layer thereon, and a low-refractive-index layer containing a refractive index lower than that of the support. anti-reflection layer.

And, it is preferred that the average reflectance (specular reflectance) of the antireflection film of the present invention at the wavelength of 380-680nm is 3% or less, and the haze value is 0.1-60% (when the antireflection film takes the light-diffusing layer and the configuration of the low refractive index layer, the haze value is 10-60%, and when the configuration includes the high refractive index layer and the low refractive index layer, the haze value is 0.1-5%), more preferably the average reflection The ratio is 2% or less and the haze value is 0.2-55% (in the case of taking the configuration of the light-diffusing layer and the low-refractive index layer, the haze value is 10-55%, and when taking the high-refractive-index layer In the case of layer and low-refractive-index layer configurations, the haze value is 0.2-4%). The degree of haze value varies greatly with the antireflection mechanism.

By specifying the range of the optical characteristics of the antireflection film above, a high-grade image display can be obtained, for example, the picture does not look whitish and the blurring of the image display can be prevented, and the decrease in contrast and the fluctuation of the color tone due to the change in viewing angle can be sufficiently suppressed , There is no reflection of external light and glare of the picture, and it is excellent in preventing reflection.

In the wavelength region of 380-780nm, use a spectrophotometer to measure the specular reflectance with an incident angle of 5° and an exit angle of -5°, and calculate the average reflectance in the wavelength region of 450-650nm. The specular reflectance at an angle of incidence of 5° is the ratio of the intensity of light reflected by the sample at -5° from the normal direction to that incident at +5° from the normal direction, and it becomes a measure of the specular reflection of the background specularly .

(light diffusion layer)

The light-diffusing layer of the present invention comprises at least one kind of translucent particles having an average particle size of 0.5-7 μm dispersed in a translucent resin, the difference in refractive index between the translucent particles and the translucent resin is 0.02-0.2, and the translucent The ratio of the transparent particles to the total solid content of the light-diffusing layer is 3-30% by weight. Also included in the translucent particles are particles of the internal diffusion series that substantially have no light-diffusing effect due to surface unevenness.

(translucent particles)

The translucent particles of the present invention are monodisperse particles with an average particle diameter of 0.5-7.0 μm, preferably 1.5-4.0 μm. The translucent particles may be particles of organic compounds or inorganic compounds. When the average particle diameter is less than 0.5 μm, the light-diffusing effect becomes small, and when the average particle diameter exceeds 7.0 μm, the film thickness becomes thick and the rolling of the film increases, and the light-diffusing effect also becomes small.

The smaller the change in particle size, the smaller the scattering characteristics, so the design of the haze value becomes easier.

The translucent particles are not particularly limited as long as the transparency of the translucent particles is high, and the difference in refractive index between the translucent particles and the translucent resin is within the above numerical range. For example, as organic fine particles, polymethyl methacrylate beads (refractive index: 1.49), acryl-styrene copolymer beads (refractive index: 1.54), melamine beads (refractive index: 1.57), polycarbonate Ester beads (refractive index: 1.57), cross-linked polystyrene beads (refractive index: 1.61), polyvinyl chloride beads (refractive index: 1.60), and benzoguanamine-melamine-formaldehyde beads (refractive index: 1.68).

As the inorganic fine particles, silica beads (refractive index: 1.44) and alumina beads (refractive index: 1.63) are exemplified. In order to prevent precipitation and lowering of the refractive index, hollow inorganic beads are also preferably used.

The difference in refractive index between the translucent particles and the translucent resin is 0.02-0.20, particularly preferably 0.04-0.10. When the difference is greater than 0.20, the film becomes white cloudy, and when it is less than 0.02, a sufficient light-diffusing effect cannot be obtained. Similar to the refractive index, when the amount of translucent particles added to the translucent resin is too large, the film becomes white and turbid, and when the added amount is too small, a sufficient light-diffusing effect cannot be obtained, so the translucent particles occupy light The proportion of the total solids content of the diffusing layer is 3-30% by weight, particularly preferably 5-20% by weight.

Two or more different translucent particles can be mixed and used. When two or more kinds of translucent particles are used, in order to effectively control the refractive index by a mixture of several kinds of particles, the difference in refractive index between the translucent particle with the highest refractive index and the translucent particle with the lowest refractive index is preferable It is 0.02-0.10, particularly preferably 0.03-0.07. The anti-glare performance can be imparted to the light-diffusing layer through translucent particles with a larger particle size, and other optical properties can also be imparted to the light-diffusing layer through translucent particles with a smaller particle size. For example, when an antireflection film is attached to a high-precision display of 133 ppi or more, it is required that the film has no defect in optical performance called glare. Due to the unevenness of the film surface, the pixel expands or shrinks, resulting in a loss of brightness uniformity, which in turn causes glare (attributable to anti-glare performance), but the combination of translucent particles that provide anti-glare performance by using a particle size ratio With translucent particles having a small particle size and a refractive index different from that of the translucent resin, the glare can be greatly improved.

When such translucent particles are added, since the translucent particles are easily precipitated in the translucent resin, an inorganic filler such as silica may be added in order to prevent precipitation. The larger the amount of inorganic filler, the more effective the anti-sedimentation of translucent particles. However, too large an amount of the inorganic filler is detrimental to the transparency of the light-diffusing layer. Therefore, it is preferable to use an inorganic filler having a particle diameter of 0.5 μm or less in an amount that does not impair the transparency of the light-diffusing layer, for example, less than about 0.1% by weight.

(translucent resin)

As the translucent resin forming the light-diffusing layer, resins curable by ultraviolet rays or electron beams, that is, (1) ionizing radiation curable resins, (2) ionizing radiation curable resins mixed with thermoplastic resins and solvents are preferably used mainly. , and (3) thermosetting resins.

The thickness of the light-diffusing layer is usually about 0.5-50 μm, preferably 1-20 μm, more preferably 2-10 μm.

The refractive index of the translucent resin is preferably 1.51-2.00, more preferably 1.51-1.90, even more preferably 1.51-1.85, particularly preferably 1.51-1.80. The refractive index of the translucent resin is a value obtained by measuring a translucent resin containing no translucent particles.

(1) As ionizing radiation curable resins, there are exemplified oligomers or prepolymers such as (meth)acrylates of polyfunctional compounds (acrylic esters and methacrylates are collectively referred to as (meth)acrylates later in this specification. acrylates), for example, preferably resins with acrylate-based functional groups such as relatively low molecular weight polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins alkyd resins, spiroacetal resins, polybutadiene resins , polythiol polyene resins and polyols. When using them, 3-30 parts by weight of a reactive diluent is added to 100 parts by weight of ionizing radiation curable resin.

As reactive diluents, monofunctional monomers and polyfunctional monomers, such as ethyl (meth)acrylate, ethylhexyl (meth)acrylate, styrene, vinyltoluene and N-vinylpyrrolidone, such as , trimethylolpropane tri(meth)acrylate, EO-modified trimethylolpropane tri(meth)acrylate; ditrimethylolpropane tetra(meth)acrylate, hexanediol (meth)acrylate base) acrylate, tripropylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate base) acrylate, a mixture of dipentaerythritol hexa(meth)acrylate and penta(meth)acrylate, 1,6-hexanediol di(meth)acrylate and neopentyl glycol di(meth)acrylate ester.

Of these reactive diluents, in particular, polyfunctional monomers can also be used alone or in combination with a binder without the above resins.

Particularly in the present invention, it is preferable to use urethane acrylate as an oligomer and dipentaerythritol hexa-(meth)acrylate as a monomer, and to use them in combination.

When an ionizing radiation curable resin is used as the ultraviolet curable resin, a photopolymerization initiator such as acetophenones, benzophenones, Michler's benzoyl-benzoate, α-amyl oxime Esters, thioxanthones such as 1-hydroxycyclohexyl phenyl ketone and 2-methyl-1-[4-(methyl-thio)phenyl]-2-morpholinopropane, and photosensitizers , for example, n-butylamine, triethylamine, tri-n-butylsulfone and DETX-S, are mixed into the ionizing radiation curable resin.

As a commercially available photoradical polymerization initiator, KAYACURE produced by Nippon Kayaku Co., Ltd. (for example, DETX-S, BP-100, BDMK, CTX, BMS, 2-EAQ, ABQ, CPTX, EPD, ITX, QTX, BTC, MCA, etc.), Irgacure produced by Ciba GeigyJapan Limited (for example, 651, 184, 500, 907, 369, 1173, 2959, 4265, 4263, etc.), and Esacure produced by Sartomer Company Inc. (KIP100F, KB1, EB3, BP, X33, KT046, KT37, KIP150 and TZT).

(2) The ionizing radiation curable resin mixed with a thermoplastic resin and a solvent is a mixture comprising 20-100 parts by weight of a thermoplastic resin and 20-400 parts by weight of a solvent mixed into 100 parts by weight of an ionizing radiation curable resin.

Examples of thermoplastic resins include cellulose ester resins (for example, nitrocellulose, acetyl cellulose, cellulose acetate propionate, ethyl hydroxyethyl cellulose, etc.), vinyl chloride resins, vinyl acetate resins, ABS resin, polyacetal, polycarbonate, polystyrene, polymethyl methacrylate, polyphenylene ether, polyamide, polyethylene terephthalate and olefin resin.

Specifically, as the thermoplastic resin, any commonly used thermoplastic resin can be used, but from the viewpoints of adhesiveness with cellulose acylate film as a support, and transparency of the formed film, cellulose resins such as nitrocellulose Base cellulose, acetyl cellulose, cellulose acetate propionate, ethyl hydroxyethyl cellulose, etc.

As the solvent, solvents for transparent resins shown below are preferably used.

(3) Thermosetting resins include, for example, phenolic resins, urea resins, diallyl phthalate resins, melamine resins, guanamine resins, unsaturated polyester resins, polyurethane resins, epoxy resins, amino alkyd resins , Melamine-urea co-condensation resins, polysiloxane resins and polysiloxane resins.

If necessary, conventionally known compounds (for example, curing agent and curing accelerator) are added to the thermosetting resin, such as curing agent, for example, crosslinking agent (for example, epoxy compound, polyisocyanate compound, polyol compounds, polyamine compounds, melamine compounds, etc.) and polymerization initiators (e.g., azobis compounds, organic peroxide compounds, organic halogen compounds, _salt compounds, etc.), and polymerization accelerators (e.g., organometallic compounds, acid compounds, base compounds, etc.). Specifically, compounds described in Shinzo Yamashita and Tosuke Kaneko, Kakyozai Handbook (Crosslinking Agent Handbook), Taiseisha Co. (1981) are exemplified. These compounds are preferably used in an amount of 0.01 to 30 parts by weight relative to 100 parts by weight of the thermosetting resin used.

Also, a monomer having a high refractive index and/or metal oxide ultrafine particles having a high refractive index may be added to the translucent resin.

As examples of high refractive index monomers, bis(4-methacryloylthiophenyl)sulfide, vinylnaphthalene, vinylphenylsulfide, and 4-methacryloyloxyphenyl- 4'-Methoxy-phenylsulfide.

As metal oxide ultrafine particles having a high refractive index, those having a refractive index of 1.70 to 2.80 and an average particle diameter of primary particles of 3 to 150 nm are preferable. If the refractive index of the particles is less than 1.70, the effect of increasing the refractive index of the film is small, and if the refractive index is greater than 2.80, the ultrafine particles may be colored, so it is not preferable. When using particles with an initial average particle diameter greater than 150 nm, the haze value of the formed light-diffusing layer becomes high and the transparency of the light-diffusing layer will be impaired, while from the perspective of maintaining a high refractive index, an initial average particle size of less than 3 nm diameter is not preferred. In the present invention, more preferable metal oxide ultrafine particles are particles having a refractive index of 1.80-2.80 and an initial average particle diameter of 3-100 nm, and even more preferable ultrafine particles are particles having a refractive index of 1.80-2.80 and an initial average particle diameter of 3-100 nm. Particles with a particle size of 5-80nm.

Preferable ultrafine metal oxide particles having a high refractive index include oxides containing Ti, Zr, Ta, In, Nd, Sn, Sb, Zn, La, W, Ce, Nb, V, Sm, or Y. , composite oxide or sulfide as the main component of particles. The main component used here refers to the component with the largest content (% by weight) among the components constituting the particles. The present invention preferably uses particles containing oxides or composite oxides containing at least one metal element selected from Ti, Zr, Ta, In, and Sn as a main component. The metal oxide ultrafine particles used in the present invention may contain various elements, for example, Li, Si, Al, B, Ba, Co, Fe, Hg, Ag, Pt, Au, Cr, Bi, P and S.

As specific examples of metal oxide ultrafine particles, ZrO ₂ , TiO ₂ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , Sb ₂ O ₃ and ITO are cited. Of these particles, ZrO ₂ is most preferably used.

Metal oxide ultrafine particles may be surface-treated. The surface treatment is carried out with inorganic compounds and/or organic compounds to change the surface properties of the particles, adjust the surface wetting properties of the metal oxide ultrafine particles, thereby better atomize in organic solvents, and improve the particles in the formation of light Dispersibility and dispersion stability in the composition of the diffuser layer. Examples of inorganic compounds that impart physicochemical adsorption properties to the particle surface include silicon-containing inorganic compounds (SiO ₂ , etc.), aluminum-containing inorganic compounds (Al ₂ O ₃ , Al(OH) _{3 ,} etc.), cobalt-containing inorganic compounds (CoO ₂ , Co ₂ O ₃ , Co ₃ O ₄ , etc.), zirconium-containing inorganic compounds (ZrO ₂ , Zr(OH) ₄ , etc.), and iron-containing inorganic compounds (Fe ₂ O ₃ , etc.).

As examples of organic compounds used for surface treatment, surface property modifiers with inorganic fillers such as known metal oxides and inorganic pigments, etc., for example, Ganryo Bunsan Anteika to Hyomen Shori Gijutsu Hyoka (Pigment Dispersion Stability and Surface Treatment Compounds described in Chapter 1, Gijutsu Joho Kyokai (2001) publication.

Specifically, organic compounds and coupling compounds having polar groups compatible with the surface of metal oxide ultrafine particles are exemplified.

Examples of polar groups compatible with the surface of metal oxide ultrafine particles include, for example, carboxyl groups, phosphono groups, hydroxyl groups, mercapto groups, cyclic acid anhydride groups, and amino groups, and compounds having at least one polar group in the molecule are preferred . For example, long-chain aliphatic carboxylic acids (e.g., stearic acid, lauric acid, oleic acid, linoleic acid, linolenic acid, etc.), polyol compounds (e.g., pentaerythritol triacrylate, dipentaerythritol pentaacrylate, ECH-modified Glycerol triacrylate, etc.), compounds containing phosphono groups (for example, EO-(propylene oxide)-modified phosphate triacrylate, etc.), and alkanolamines (for example, ethylenediamine EO adducts ( 5mol), etc.).

As the coupling compound, known organometallic compounds including silane coupling agents, titanate coupling agents and aluminate coupling agents are exemplified. Most preferred are silane coupling agents. Specifically, compounds disclosed in paragraphs [0011] to [0015] of JP-A-2002-9908 and JP-A-2001-310423 are exemplified.

Relative to 100 parts by weight of the translucent resin, the amount of the high refractive index monomer and/or the high refractive index metal oxide ultrafine particles added is preferably 10-90 parts by weight, more preferably 20-80 parts by weight.

It is preferable that the light-diffusing layer contains an organosilyl compound represented by formula a, and/or a hydrolyzate of an organosilane compound and/or a partial condensate of the hydrolyzate, as the surface adhesive.

As specific examples of surface adhesives, for example, KBM-5103 and KBM-503 (commercial products, produced by Shin-Etsu Chemical Co., Ltd.), and/or their hydrolyzate, and/or the hydrolyzate Partial condensates of are preferred compounds.

The surface adhesive is preferably added in an amount of 1-50 parts by weight, more preferably 2-30 parts by weight, relative to 100 parts by weight of the total solid content of the light-diffusing layer-forming composition.

Also, it is preferable to add a surfactant to the light-diffusing layer in order to improve the surface uniformity of the antireflection film of the present invention. As examples of surfactants, for example, perfluoroalkyl-substituted (meth)acrylate copolymers having 6 to 12 carbon atoms, and perfluorovinyl ether copolymers having 6 to 12 carbon atoms .

The surfactant is added in an amount of preferably 0.01-20 parts by weight, more preferably 0.1-10 parts by weight, relative to 100 parts by weight of the total solid content of the light-diffusing layer-forming composition.

A method of forming a light-diffusing layer on a support is described below.

In the present invention, the light-diffusing layer is formed by coating a light-diffusing layer-forming composition on a support and drying it, wherein the composition is formed by dissolving and dispersing a transparent resin, transparent particles, and Prepared with various additives as required.

The solvent for coating can be arbitrarily selected from water and organic solvents, and a liquid having a boiling point of 50°C or higher is preferable as a coating solvent, and an organic solvent having a boiling point of 60-180°C is more preferable.

Examples of organic solvents include alcohols, ketones, esters, amides, ethers, ether esters, hydrocarbons and halogenated hydrocarbons. Specifically, alcohols (for example, methanol, ethanol, propanol, butanol, benzyl alcohol, ethylene glycol, propylene glycol, ethylene glycol monoacetate, etc.), ketones (for example, methyl ethyl ketone , methyl isobutyl ketone, cyclohexanone, methyl cyclohexanone, etc.), esters (for example, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl formate, propyl formate, formic acid butyl ester, ethyl lactate, etc.), aliphatic hydrocarbons (such as hexane, cyclohexane, etc.), halogenated hydrocarbons (such as methyl chloroform, etc.), aromatic hydrocarbons (such as benzene, toluene, xylene etc.), amides (for example, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc.), ethers (for example, dioxane, tetrahydrofuran, ethylene glycol dimethyl ether, propylene glycol dimethyl base ether, etc.), ether alcohols (for example, 1-methoxy-2-propanol, ethyl cellosolve, methyl carbinol, etc.). These solvents may be used alone or in combination of two or more solvents. Preferred dispersion media are toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol. It is also preferable to use a coating solvent mainly containing a ketone solvent (for example, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.).

Light diffusion can be formed by known film forming methods such as dip coating, air knife coating, curtain coating, roll coating, wire rod coating, gravure coating, micro gravure coating or extrusion coating The composition of the layer is applied, the coating is allowed to stand until the surface unevenness configuration of the translucent layer sufficient to form the first and second translucent particles, dried, and irradiated with light and/or heat to form a light diffusing layer .

Coating methods by microgravure coating methods are particularly preferred.

The micro-gravure coating method used in the present invention is such a coating method that the diameter of the gravure roll used is about 10-100 mm, preferably about 20-50 mm, and engraved with a gravure pattern around it, and the gravure roll is placed under the support Rotate in the opposite direction to the running direction of the support, while wiping off the excess coating liquid on the surface of the gravure roller with a scraper, and transfer a specified amount of coating liquid to the lower part of the support at the position where the upper part of the support is in a free state. The support in the roll is continuously unrolled, and at least one of a hard coat layer containing a fluoropolymer and a low-refractive index layer may be coated on one side of the unrolled support by a microgravure coating method.

As the coating conditions of the micro-gravure coating method, the number of lines of the gravure pattern engraved on the gravure roll is preferably 50-800 lines/inch, more preferably 100-300 lines/inch, and the depth of the gravure pattern is preferably 1-600 μm , more preferably 5-200 μm, the rotational speed of the gravure roll is preferably 3-800 rpm, more preferably 5-200 rpm, the running speed of the support is preferably 0.5-100 m/min, more preferably 1-50 m/min.

The coating composition is preferably irradiated with light to accelerate curing of the light-transmitting resin. It is also preferable to perform heat treatment in the second half of the photocuring treatment. Drying may be performed by air drying at a low temperature of about room temperature or may be performed by heating. The heating temperature is 40-180°C, preferably 80-150°C. The drying time is preferably 0.5-60 minutes.

The light source for light irradiation may be any of electron beams, ultraviolet rays, and near infrared rays. For example, in the case of electron beam curing, there are listed energies of 50-1,000 KeV, preferably 100-300 KeV, from various electron beam accelerators, for example, Cockcroft Walton type, VanDe Graaff type, resonant transformer type, insulating core transformer type, Electron beams emitted from linear, Dynamitoron type and high frequency type accelerators, and in the case of ultraviolet curing, e.g. from ultra high pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, carbon arc, xenon arc and metal halide lamps of ultraviolet light. As a light source for ultraviolet rays, various available laser sources with a wavelength of 350-420nm can be used, for example, ultra-high pressure, high pressure, medium pressure and low pressure mercury lamps, chemical lamps, carbon arc lamps, metal halide lamps, xenon lamps, and sunlight, Can be made into multiple beams for irradiation. As a light source of near-infrared rays, a halogen lamp, a xenon lamp, and a high-pressure sodium lamp are exemplified, and various available laser sources with a wavelength of 750-1,400 nm can be made into multiple beams for irradiation.

In the case of photoradical polymerization by light irradiation, polymerization can be performed in air and inert gas, but in order to shorten the polymerization induction period of the radical polymerizable monomer or sufficiently increase the polymerization rate, it is preferable to make the oxygen concentration in the atmosphere as low as possible. probably low. The intensity of ultraviolet irradiation is preferably around 0.1-100 mW/cm ² , and the irradiation amount on the coating surface is preferably 100-1,000 mJ/cm ² . Preferably, the temperature distribution of the coating during light irradiation is controlled as uniform as possible, preferably within ±3°C, more preferably within ±1.5°C. In this temperature range, the polymerization reactions in the in-plane direction and the depth direction in the layer proceed uniformly.

(high refractive index layer and medium refractive index layer)

Preferred embodiments of the high-refractive-index layer and the medium-refractive-index layer in the fourth embodiment are the same as in the third embodiment.

The antireflection film in the fourth embodiment may further contain a hard coat layer, a transparent antistatic layer, a primer layer, an electromagnetic shielding layer, an undercoat layer, and a protective layer.

(hard coat)

According to need, a hard coat layer is used to impart physical strength to the antireflection film, and it is preferable to place the hard coat layer between the support and the light-diffusing layer. The hard coat layer is preferably formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound. Therefore, ionizing radiation curable polyfunctional monomers and polyfunctional oligomers are preferably used in the coating composition. As the polymerizable functional group, unsaturated polymerizable functional groups such as (meth)acryloyl, vinyl, styryl and allyl are exemplified. A (meth)acryloyl group is especially preferred. Specifically, those described above in detail in the transparent resin of the light-diffusing layer are preferred.

The hard coat layer preferably contains inorganic fine particles having an average primary particle diameter of 200 nm or less. As specific examples of the inorganic fine particles, the inorganic fine particles mixed in the cellulose acylate film described above are preferably used.

An oligomer or a polymer having a weight average molecular weight of 500 or more, or an oligomer and a polymer, may be added to the hard coat layer to impart brittleness. As oligomers and polymers, (meth)acrylate-, cellulose- and styrene-based polymers, urethane acrylates and polyester acrylates are cited. Poly(glycidyl(meth)acrylate) and poly(allyl(meth)acrylate) having functional groups in side chains are preferred.

The content of oligomer or polymer, or oligomer and polymer in the hard coat layer is preferably 5-80% by weight, more preferably 25-70% by weight, especially preferably 35-65% by weight of the total weight of the hard coat layer .

The strength of the hard coat layer by the pencil hardness test of JIS K5400 is preferably H or higher, more preferably 2H or higher, most preferably 3H or higher.

Also, in the Taber's test according to JIS K5400, the smaller the abrasion amount of the sample piece before and after the test, the better the sample.

When the hard coat layer is formed by a crosslinking reaction or polymerization reaction of an ionizing radiation curable compound, the crosslinking reaction or polymerization reaction is preferably performed in an atmosphere having an oxygen concentration of 10% by volume or less. A hard coat excellent in physical strength and chemical resistance can be formed by performing the reaction in an atmosphere having an oxygen concentration of 10% by volume or less.

Crosslinking of ionizing radiation curable compounds is preferably carried out in an atmosphere having an oxygen concentration of 6% by volume or less, more preferably 4% by volume or less, particularly preferably 2% by volume or less, most preferably 1% by volume or less reaction or polymerization. As a mode of making the oxygen concentration 10% by volume or less, it is preferable to replace the atmosphere with another gas (nitrogen concentration: about 79% by volume and oxygen concentration: about 21% by volume), and it is particularly preferable to replace the atmosphere with nitrogen gas (nitrogen rinse).

The hard coat layer is preferably formed by coating a coating composition for forming a hard coat layer on the surface of a transparent support.

As the coating solvent, ketone solvents such as methyl ethyl ketone, isobutyl ketone, and cyclohexanone shown in the high-refractive index layer are preferable from the viewpoint of adhesive performance. Solvents other than ketone solvents may also be contained. The content of the ketone solvent is preferably 10% by weight or more of the total solvent contained in the coating composition, more preferably 30% by weight or more, even more preferably 60% by weight or more.

The thickness of the hard coat layer is preferably 0.3-20 μm, more preferably 0.6-10 μm.

(transparent antistatic layer)

From the standpoint of antistatic on the surface of the film, the present invention preferably provides a transparent antistatic layer between the support and the light-diffusing layer containing the conductive material. In order to protect the outer surface energy of the polarizing plate on the visible end provided on the IPS mode and VA mode displays of the liquid crystal mode, it is preferable to provide a conductive layer as a transparent antistatic layer.

The transparent antistatic layer can be formed by a conventionally known method, for example, a method of coating a conductive coating liquid containing conductive fine particles and an active curable resin, a method of forming a hardened film of a conductive polymer, and a method of depositing or sputtering A method of forming a conductive film by spraying metal or metal oxide to form a transparent film.

As the conductive fine particles, fine particles made of metal oxides or nitrides are preferable. As examples of metal oxides or nitrides, tin oxide, indium oxide, zinc oxide, and titanium nitride are cited. Particular preference is given to tin oxide and indium oxide.

The thickness of the transparent antistatic layer is preferably 0.01-10 μm, more preferably 0.03-7 μm, even more preferably 0.05-5 μm.

The surface resistance of the transparent antistatic layer is preferably 2×10 ¹² Ω/□ or less, more preferably 10 ⁵ -10 ¹² Ω/□, even more preferably 10 ⁵ -10 ⁹ Ω/□, most preferably 10 ⁵ -10 ⁸ Ω/□. The surface resistance of the transparent antistatic layer can be measured according to the four-probe method.

The haze value of the transparent antistatic layer is preferably 25% or less, more preferably 20% or less, most preferably 15% or less. The light transmittance of the transparent antistatic layer for light having a wavelength of 550 nm is preferably 50% or more, more preferably 60% or more, most preferably 70% or more. It is a value obtained by subtracting the measured value of the sample before coating from the measured value of the sample after coating the antistatic layer. By arranging different functional layers on the antistatic layer, the haze value and light transmittance often fluctuate greatly.

(surface configuration of transparent antistatic layer)

It is preferred that the surface of the transparent antistatic layer formed by the present invention has a configuration with a small surface roughness of a size without optical influence, and according to JIS B0601-1994, the arithmetic mean roughness value (Ra) of the surface roughness of the film is 0.03 μm or less, the ten-point average roughness (Rz) is 0.06 μm or less, and the maximum height (Ry) is 0.09 μm or less; more preferably the arithmetic mean roughness value (Ra) is 0.001-0.03 μm, the ten-point average The roughness (Rz) is 0.001-0.06 μm; even more preferably the arithmetic mean roughness value (Ra) is 0.001-0.015 μm, the ten-point average roughness (Rz) is 0.002-0.05 μm, and the maximum height (Ry) is 0.05 μm or less; especially preferably the arithmetic average roughness value (Ra) is 0.001-0.010 μm, the ten-point average roughness (Rz) is 0.002-0.025 μm, and the maximum height (Ry) is 0.04 μm or less.

Also, in the above minute surface roughness of the size without optical influence, it is preferable that the ratio of the arithmetic mean roughness (Ra) to the ten-point mean roughness (Rz), (Ra/Rz) is 0.15 or more, and the thin film of the thin film The average distance (Sm) of the unevenness is 2 μm or less. Here, the relationship between Ra and Rz shows the uniformity of surface roughness. It is preferable that the ratio (Ra/Rz) is 0.17 or more and the average distance (Sm) is 1-0.01 µm.

The profile of surface roughness can be evaluated with atomic force microscopy (AFM).

By embodying the configuration and distribution of the surface roughness of the entire surface of the transparent antistatic layer, an anchoring effect is uniformly and sufficiently applied to the entire surface of the film, and adhesion can be maintained even when the upper layer is continuously formed on a long film. Furthermore, adhesive properties can be retained without fluctuation after long-term storage.

The adhesive force of the transparent antistatic layer to the upper layer (light-diffusing layer) provided on the conductive cured film of the present invention is 50 mg or less in terms of abrasion amount in the Taber's abrasion test measured according to the method of JIS K-6902 . Specifically, this value corresponds to the amount of wear after 500 rotations under a load of 1 kg. The abrasion amount is preferably 40 mg or less. Within this abrasion amount range, the scratch resistance of the antireflection layer can be sufficiently maintained.

<Characteristics of Antireflection Film> (Fourth Embodiment)

(optical properties)

The average value (that is, the average reflectance) of the specular reflectance of the antireflection film of the present invention under the incident angle of 5 ° in the wavelength region of 450-650nm is 2.5% or less, preferably 1.8% or less, more preferably 1.4% or less.

The specular reflectance at an angle of incidence of 5° is the ratio of the intensity of light reflected by the sample at -5° from the normal direction to that incident at +5° from the normal direction, and it becomes a measure of the specular reflection of the background specularly . When the antireflection film is used as a film having an antiglare function, the intensity of light reflected at -5° in the normal direction becomes weak due to partial scattered light due to surface roughness provided for antiglare. Therefore, it can be said that the specular reflectance is a measurement method reflecting the influence of anti-glare performance and anti-reflection performance.

If when the wavelength region of 450-650nm is irradiated with an angle of incidence of 5°, the average value (that is, the average reflectance) of the specular reflectance of the antireflection film of the present invention is greater than 2.5%, and people feel uncomfortable to the specular reflection of the background , and visibility is disadvantageously reduced when the film is used on a surface film of a display.

By making the L* value, a ^* value and ^{b* value} of the CIE 1976L ^* a ^* b ^* color space showing the color tone of the specularly reflected light incident at an angle of 5°in the GIE standard light source D65 in the wavelength region of 380-780nm, respectively, in 3 In the range of ≤L ^* ≤20, -7≤a ^* ≤7 and -10≤b ^* ≤10, the hue of the reflected light from magenta to blue-purple is reduced, and the hue of these reflected light is reduced in the multilayer antireflection film There is a problem in . Furthermore, the color tone is sharply lowered by setting the L ^* , a ^*, and b ^* values in the ranges of 3≤L ^* ≤10, 0≤a ^* ≤5, and -7≤b ^* ≤0, respectively. When the film is used for a liquid crystal display, the color tone is neutral when high brightness external light such as a fluorescent lamp is slightly specularly reflected indoors without being uncomfortable at all. In detail, the reddish hue is strong when a ^* >7, and the cyan hue is thick when a ^* <-7, and they are not preferable. The light blue hue is strong when the b ^* value is b ^* <-7, and the light yellow hue is strong when the b ^* value is b ^* >0, neither of which is preferable.

In the present invention, it is preferable that each value of L ^* , a ^* and b ^* is constant over the entire display image, specifically, it is preferable that the rate of change of each value in the plane is 20% or less, more preferably 8%. or smaller. When the rate of change is within this range, uniform anti-reflection performance and good visibility can be secured.

Specular reflectance and color tone were measured with a spectrophotometer V-50 (manufactured by JASCO Corporation) equipped with an adapter ARV-474. The anti-reflection performance can be evaluated by measuring the specular reflectance at an incident angle of 5° and an output angle of -5° in the wavelength region of 380-780nm, and calculating the average reflectance in the wavelength region of 450-650nm. Moreover, the hue of reflected light can be evaluated by calculating the L ^* value, a ^* value, and b ^* value of the CIE 1976L ^* a ^* b ^* color space, and the L ^* value, a ^* value, and b ^* value show the reflection spectrum from the measured The hue of the specularly reflected light of the incident light irradiated at an angle of 5° by the CIE standard illuminant D65.

By suppressing the fluctuation width of the thickness of the cellulose acylate support within the above range, by suppressing the hue and fluctuation width of the support itself within the above range, and by forming The antireflection layer without coating unevenness can greatly reduce the unevenness of the color tone of reflected light caused by the unevenness of the thickness of the antireflection film.

The color tone of reflected light is more neutral, and the antireflection film is excellent in weather resistance.

The uniformity of the color tone of the reflected light can be found from the reflection spectrum of the reflected light in the wavelength region of 380-680 nm. The ratio of change in hue is obtained by finding the a ^* and b ^* mean values, respectively, on the L ^* a ^* b ^* chromaticity diagram, and dividing the difference (ΔA) between the maximum and minimum values of the a ^* value and b ^* value by the mean value and multiplied by 100. The rate of change is preferably 30% or less, more preferably 20% or less, most preferably 8% or less.

ΔE, which is the change in color tone of the antireflection film of the present invention before and after the weathering test, is preferably 15 or less, more preferably 10 or less, most preferably 5 or less.

When the antireflection film has such a hue, the change in average reflectance of the antireflection film in the wavelength region of 380-680 nm before and after the weathering test is preferably 0.4% or less, more preferably 0.2% or less.

When the change in average reflectance is within this range, low reflection can be compatible with the reduction in the color tone of reflected light, and is preferable, for example, when the antireflection film is used on the outermost surface of an image display, at high brightness The color tone is neutral and the level of the displayed image is increased in the case of a slight specular reflection of ambient light such as a fluorescent lamp indoors.

The antireflection film of the present invention is characterized in that these optical and mechanical properties hardly change even after a weathering test. Specifically, the antireflection film is characterized in that changes in these characteristics after a weathering test are suppressed.

The weather resistance test of the present invention is a weather resistance test measured according to JIS K5600-7-7: 1999, and refers to a method using a sunlight weather resistance test box (S-80, produced by Suga Test Instruments Co., Ltd.) at 50 Weathering test for 150 hours treatment time at % humidity.

The light-reflecting antireflection film having such a neutral tone and low reflectance can be obtained by optimizing the balance of the refractive index of the low-refractive index layer used in the light-diffusing layer and the refractive index of the translucent resin.

In order to control moisture permeability, the surface free energy of the antireflective film of the present invention is preferably 15-26mN/m and the coefficient of dynamic friction is 0.05-0.20, more preferably the surface free energy is 17-22mN/m and the coefficient of kinetic friction is 0.07-0.15.

(conductivity)

It is preferable that the antireflection film of the present invention has the underlying conductivity regardless of the front and back liquid crystal modes.

That is, it is preferable that the vertical peeling charge measured with triacetylcellulose (TAC) or polyethylene terephthalate (PET) at normal temperature and humidity is from -200pc (picocoulomb)/ ^cm to +200pc (picocoulomb) )/cm ² , more preferably from -100 pc/cm ² to +100 pc/cm ² , even more preferably from -50 pc/cm ² to +50 pc/cm ² . Here, the unit pc (picocoulomb) is 10 ^-12 coulomb.

More preferably, the vertical peel charge measured at normal temperature and 10% RH is from -100 pc/cm ² to +100 pc/cm ² , more preferably from -50 pc/cm ² to +50 pc/cm ² , most preferably 0 pc/cm ² .

The measurement method of vertical peeling charge is as follows.

The measurement sample is left to stand for 2 hours or longer in the environment of the measurement temperature and humidity in advance. The measurement device includes a table on which a measurement sample is placed, a head which holds an opposing film and is capable of repeatedly pressing and peeling the measurement sample from the upper end, and an electrometer coupled to the head for measurement of electrification. The antireflective film to be measured is placed on the bench, and TAC or PET is adhered to the head. The measured portion of the sample is destaticized and the head is repeatedly pressed and peeled against the sample, the charge values are read at the time of the first peel and the time of the fifth peel and these values are averaged. Repeat this step for 3 new samples, average all values and charge them as vertical peel.

There are cases where the sample is charged in a positive or negative amount depending on the relative film and the type of sample being measured, but the question is the magnitude of the absolute value.

Also, the absolute value of charge generally becomes larger in a low-humidity environment. Since the antireflection film of the present invention is also small in this absolute value, the film is therefore preferable as a protective film for a polarizing plate.

By making the absolute value of the vertical peeling charge at normal temperature and 10% RH within the above range, the antireflection film of the present invention is excellent in dustproofness and thus is preferable.

By adjusting the ratio of various elements on the surface of the antireflection film, the absolute value of the vertical peeling charge can be made within the above range.

When using the antireflection film of the present invention as a polarizer on the visible end of a liquid crystal display of liquid crystal mode such as TN or OCB, the surface resistance value of the protective film is preferably 1×10 ¹¹ Ω/□ or more. By making the absolute value of the vertical peeling charge small, the level of image display is not lowered while maintaining the dustproofness. The method of measuring the surface resistance value is the disc electrode method described in JIS. That is, the current value 1 minute after the voltage application was read, and thus the surface resistance value (SR) was found.

<transparent support>

Preference is given to using plastic films as transparent supports for the antireflection films of the invention. Examples of polymers that form plastic films include cellulose esters (e.g., triacetyl cellulose, diacetyl cellulose), polyamides, polycarbonates, polyesters (e.g., polyethylene terephthalate, polyethylene naphthalate, glycol ester), polystyrene, polyolefin, norbornene resin (for example, Arton, trade name, produced by JSR Corporation), and amorphous polyolefin (Zeonex, trade name, produced by Zeon Corporation). Among these polymers, triacetyl cellulose, polyethylene terephthalate, and polyethylene naphthalate are preferred, and triacetyl cellulose is particularly preferred. When the antireflection film of the present invention is used for a liquid crystal display, the film is mounted on the outermost surface of the display by providing an adhesive layer or the like on one side of the film. In the case of using triacetyl cellulose as the transparent support, since triacetyl cellulose is used as the protective film for protecting the polarizing sheet of the polarizer, it is actually preferable to use the antireflection film of the present invention as the protective film in view of cost.

It is preferable that the antireflection film has a transparent substrate (transparent support), excluding the case where the antireflection film is used directly on the surface of a CRT image display and the surface of a lens. The light transmittance of the transparent substrate is preferably 80% or more, more preferably 86% or more. The haze value of the transparent substrate is preferably 2.0% or less, more preferably 1.0% or less. The refractive index of the transparent substrate is preferably 1.4-1.7. As a transparent substrate, plastic films are preferred over glass plates. Examples of materials for plastic films include cellulose esters, polyamides, polycarbonates, polyesters (e.g., polyethylene terephthalate, polyethylene naphthalate, poly-1,4-cyclohexanedi Methylene terephthalate, polyethylene-1,2-diphenoxyethane-4,4'-dicarboxylate, polybutylene terephthalate), polystyrene (e.g., syndiotactic polystyrene), polyolefins (eg, polypropylene, polyethylene, polymethylpentene), polysulfone, polyethersulfone, polyallylate, polyetherimide, polymethacrylic acid Methyl esters and polyether ketones. Among them, cellulose ester, polycarbonate, polyethylene terephthalate, and polyethylene naphthalate are preferable. Specifically, when a transparent substrate is used for a liquid crystal display, a cellulose acylate film is preferably used. Cellulose acylate is produced from cellulose by esterification.

The cellulose acylate film support of the present invention has a thickness of 30-120 μm, preferably 30-100 μm, more preferably 30-80 μm. When the film thickness is within the above range, support cracking and wrinkling are suppressed during preparation, the thickness of polarizers and displays can be reduced, and excellent optical characteristics, economic advantages, productivity and processing efficiency are ensured.

The cellulose acylate film used as a support in the present invention is a long cylindrical film with a length of 100 to 5,000 m and a width of 0.7 to 2 m. The use of this film can make the anti-reflection film polarizer, protective film and image display thinner and lighter in weight, and can stably obtain excellent optical characteristics, such as improving contrast and nominal brightness by increasing light transmittance, and can easily Wide and long supports can be easily handled without problems such as wrinkling.

The fluctuation width of the film thickness is within ±3%, preferably within ±2.5%, more preferably within ±1.5%. When the undulation width is within this range, the thickness of the support does not substantially affect the antireflection performance.

In order to make the fluctuation width of film thickness within ±3%, (1) low molecular weight polymer (oligomer) not containing cellulose acylate, (2) concentration of solution (coating dope) at the time of controlling casting and viscosity, the solution (coating dope) obtained by dissolving a polymer film-forming composition containing cellulose acylate as a main component in an organic solvent, and (3) controlling the drying temperature of the film surface and the The amount of air and the direction of air when dry air is used in the process are effective methods. The dissolution method, the casting method and the drying method are described later in the item "Production method of cellulose acylate film".

The cellulose acylate film used in the present invention has a turn-up value of -7/m to +7/m, preferably -5/m to +5/m in the width direction. When the antireflection layer is provided on the long and wide cellulose acylate film described later (for example, a long film with a length of 100-5,000 m and a width of 0.7-1.5 m), the film is easy to handle, and when in the width direction Breaking of the film is suppressed when the turn-up value is within the above range. In addition, it is possible to suppress the generation of dust caused by strong contact between the film and the conveying roller at the edge portion or the center portion, and the adhesion of foreign matter to the film, and also, the frequency of point defects and the coating of the antireflection film and polarizing plate can be suppressed. Streaks are limited to the allowed amount. By specifying the curl value to be within the above range, it is possible to prevent air bubbles from entering during sticking of the polarizing sheet.

The roll-up value can be measured according to the test method provided by the American National Standards Institute (ANSI/ASCPHI.29-1985).

As the cellulose used for the material of the cellulose acylate film of the present invention, cotton linter, kenaf and wood pulp (hardwood pulp, softwood pulp) are known, and cellulose ester obtained from any material cellulose can be used types and, where appropriate, mixtures of cellulosic materials can be used.

Cellulose acylate is produced from cellulose by esterification, however, instead of using the above particularly preferred cellulose, cotton linters, kenaf and pulp are refined and used.

In the present invention, cellulose acylate refers to carboxylic acid esters of cellulose having 2 to 22 carbon atoms in total.

As the acyl group having 2 to 22 carbon atoms used in the cellulose acylate of the present invention, an aliphatic group or an aryl group can be used without particular limitation, for example, an alkylcarbonyl ester of cellulose, a chain Alkenylcarbonyl esters, cycloalkyl-carbonyl esters, aromatic carbonyl esters, and aromatic alkylcarbonyl esters, and each of them may further have one substituent. Among these groups, acyl groups are preferred, and examples include acetyl, propionyl, butyryl, heptanoyl, hexanoyl, octanoyl, decanoyl, dodecanoyl, tridecanoyl, tetradecanoyl, hexadecanoyl, Alkanoyl, octadecanoyl, cyclohexanecarbonyl, adamantylcarbonyl, oleoyl, phenyl-acetyl, benzoyl, naphthylcarbonyl and cinnamoyl. Among these groups, more preferred acyl groups are acetyl, propionyl, butyryl, pentanoyl, hexanoyl, cyclohexanecarbonyl, dodecanoyl, octadecanoyl, oleoyl, benzoyl, naphthylcarbonyl and cinnamoyl.

The synthesis method of cellulose acylate is described in detail on page 9 of Hatsumei Kyokai Kokai Giho, Kogi No. 2001-1745 (published by Hatsumei Kyokai on March 15, 2001).

It is preferable that the degree of substitution of the hydroxyl groups of cellulose in the cellulose acylate of the present invention should satisfy the following formulas (I) and (II).

                                          (I)

0≤SA′≤3.0 (II)

Here, SA' refers to the degree of substitution of hydrogen atoms of hydroxyl groups in cellulose with acetyl groups, and SB' refers to the degree of substitution of hydrogen atoms of hydroxyl groups in cellulose with acyl groups having 3 to 22 carbon atoms. In addition, SA represents that the hydrogen atom of the hydroxyl group in cellulose is replaced by an acetyl group, and SB represents that the hydrogen atom of the hydroxyl group in the cellulose is replaced by an acyl group having 3-22 carbon atoms.

Glucose units having β-1,4 linkages constituting cellulose have free hydroxyl groups at the 2-, 3-, and 6-positions. Cellulose acylate is a polymer obtained by partially or completely esterifying these hydroxyl groups with acyl groups. The degree of substitution of the acyl group refers to the respective ratios of esterification at the 2-, 3-, and 6-positions of cellulose (100% esterification at each position is represented by a degree of substitution of 1).

In the present invention, the sum of the degrees of substitution of SA and SB (SA'+SB') is more preferably 2.6-3.0, especially preferably 2.80-3.00.

The degree of substitution (SA') of SA is more preferably 1.4-3.0, especially preferably 2.3-2.9.

It is preferable to satisfy the following equation (II') at the same time.

0≤SB″≤1.2 (II′)

Here, SB" represents the degree of substitution of an acyl group having 3 or 4 carbon atoms substituting a hydrogen atom of a hydroxyl group in cellulose.

Preferably, 28% or more of SB" are substituents of the hydroxyl group at the 6-position, more preferably 30% or more are substituents of the hydroxyl group at the 6-position, even more preferably 31% or more, especially preferably 32% or more are substituents of the hydroxyl group at the 6-position. Also, wherein the sum of the degrees of substitution of SA' and SB" at the 6-position of the cellulose acylate is 0.8 or more, preferably 0.85 or more , a cellulose acylate film of 0.90 or more is especially preferred, and is also cited as a preferred cellulose acylate film. By using these cellulose acylates, solutions having good solubility can be prepared, and specifically, preferred solutions can be prepared in chlorine-free organic solvents.

The degree of substitution can be obtained by calculation from the measurement of the degree of bonding of fatty acids bonded to hydroxyl groups in cellulose. Can be measured based on ASTM D-817-91 and ASTM D-817-96.

The substitution state of the acyl group on the hydroxyl group can be measured by ¹³ C-NMR method.

It is preferable that the polymer component constituting the cellulose acylate film of the present invention substantially comprise cellulose acylate having the above definition. "Substantially" means 55% by weight or greater, preferably 70% by weight or greater, more preferably 80% by weight or greater of the entire polymer component. Cellulose acylate may be used alone or in admixture of two or more.

The degree of polymerization of the cellulose acylate preferably used in the present invention is 200-700, preferably 230-550, more preferably 230-350, especially preferably 240-320 in terms of viscosity-average degree of polymerization. The viscosity-average degree of polymerization can be measured according to the intrinsic viscosity method of Uda et al. . Details thereof are also disclosed in JP-A-9-95538.

The number average molecular weight Mn of the cellulose acylate is preferably in the range of 7×10 ⁴ to 25×10 ⁴ , more preferably 8×10 ⁴ to 15×10 ⁴ . The ratio of the weight average molecular weights Mw to Mn of the cellulose acylate, Mw/Mn, is 1.0 to 5.0, more preferably 1.0 to 3.0. The average molecular weight and molecular weight distribution of cellulose acylate can be measured by high performance liquid chromatography, from which Mn and Mw and Mw/Mn can be calculated.

Cellulose acylate satisfying the above formulas (I) and (II) is preferably used for the cellulose acylate film of the present invention.

In order to improve the mechanical strength and dimensional stability of the film, and to improve moisture-proof performance, it is preferable that the cellulose acylate film of the present invention contains hydrophobic fine particles. From the viewpoint of suppressing the haze value, the initial average particle diameter of the fine particles is preferably 1 to 100 nm, and the apparent specific gravity of the fine particles is preferably 70 g/L or more. The fine particles are added in an amount of 0.01 to 10 parts by weight, particularly preferably 0.05 to 7 parts by weight, relative to 100 parts by weight of cellulose acylate.

Specific examples of preferable fine particles as inorganic compounds include composites containing silicon, silicon dioxide, titanium dioxide, zinc oxide, aluminum oxide, barium oxide, zirconium oxide, strontium oxide, antimony oxide, tin oxide, tin oxide- Antimony, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate, calcium phosphate, ITO, and zinc antimonate. Inorganic compounds containing silicon and zirconia are more preferred. In order to suppress an increase in the haze of the cellulose acylate film, it is particularly preferable to use silica.

The fine particles are preferably surface-treated with a hydrophobizing treatment. As the surface treatment compound, an organic compound having a polar group having an affinity with the surface of fine particles and a coupling agent are preferably used.

(plasticizer)

A plasticizer is an added component that imparts flexibility to the cellulose acylate film, improves dimensional stability and moisture resistance, and reduces curling. As the plasticizer used in the present invention, conventionally known plasticizers as plasticizers for cellulose acylate may be mixed and used. As these conventional plasticizers, for example, phosphate plasticizers, phthalate plasticizers, and glycolate plasticizers can be preferably used. As the phosphate ester plasticizer, triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, diphenyl vinyl phosphate, trioctyl phosphate and phosphoric acid Tributyl; As phthalate plasticizers, diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, di Octyl esters, dibutyl phthalate and di-2-ethylhexyl phthalate; as glycolate plasticizers, butyl phthaloyl butyl glycolate, glycolic acid Ethylphthaloyl ethyl ester and methyl phthaloyl ethyl glycolate. It is preferable that the plasticizer is stably dispersed in the film, has excellent bleeding properties and is hardly hydrolyzable.

As more preferable plasticizers for use in the present invention, plasticizers having a boiling point of 200°C or higher and being liquid at 25°C, and solids having a melting point of 25 to 250°C are exemplified. As even more preferable plasticizers, plasticizers having a boiling point of 250°C or more and being liquid at 25°C, and solids having a melting point of 25 to 200°C are exemplified. When the plasticizer is liquid, it is purified by distillation under reduced pressure, and the higher the degree of vacuum, the more preferable. In the present invention, it is particularly preferable to use a plasticizer having a vapor pressure of 1,333 Pa or less at 200°C, more preferably a compound having a vapor pressure of 667 Pa or less, even more preferably 133-1 Pa.

In order to improve the adhesive performance, it is preferable that the cellulose acylate film of the present invention has 20-300 (g/m ² , 24h, 25°C, 90% RH), more preferably 20-260 (g/m ² , 24h, 25°C , 90% RH), most preferably a moisture permeability of 20-200 (g/m ² , 24h, 25°C, 90% RH).

The exudation property of the present invention refers to the property of reducing the weight of the film caused by additives, such as plasticizers, being precipitated or evaporated from the film under high temperature and high humidity environment. Specifically, the weight of the sample was measured after the sample was left to stand at 23°C, 55% RH for 1 day, and then the sample was left to stand at 80°C, 90% RH for 2 weeks, and then at 23°C, 55% RH. After standing for 1 day under RH, the weight of the sample was measured and the exudation performance was calculated by the equation shown below:

Exudation property={(weight of sample before treatment-weight of sample after treatment)/weight of sample before treatment}×100(%)

The exudation property is preferably 2.0% or less, more preferably 1.0% or less, even more preferably 0.5% or less, especially preferably 0.1% or less.

Next, the aliphatic polyhydric alcohol esters used as the plasticizer in the present invention are described in detail. The aliphatic polyol esters of the present invention are esters of divalent or higher aliphatic polyols and one or more monocarboxylic acids.

(aliphatic polyol)

The aliphatic polyols used in the present invention are divalent or higher alcohols and are represented by the following formula (7):

R ¹ -(OH)n

wherein R ¹ represents an n-valent aliphatic organic group, n represents an integer of 2 or more, and each of the plurality of OH groups represents an alcohol or a phenolic hydroxyl group.

Examples of n-valent aliphatic organic groups include alkylene (for example, methylene, ethylene, trimethylene, tetramethylene), alkenylene (for example, vinylene), alkynylene (eg, ethynylene), cycloalkylene (eg, 1,4-cyclohexanediyl), alkanetriyl (eg, 1,2,3-propanetriyl). The n-valent aliphatic organic groups include those n-valent aliphatic groups having one substituent (eg, a hydroxyl group, an alkyl group, a halogen atom). n is preferably 2-20.

Examples of preferred polyols include, for example, adonitol, arabitol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol Alcohol, tripropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, dibutylene glycol, 1,2,4-butanetriol, 1,5-pentanediol Alcohol, 1,6-hexanediol, hexanetriol, galactitol, mannitol, 3-methylpentane-1,3,5-triol, pinacol, sorbitol, trimethylol Propane, trimethylolethane and xylitol. Particular preference is given to triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, sorbitol, trimethylolpropane and xylitol.

(monocarboxylic acid)

The monocarboxylic acid of the polyol ester of the present invention is not particularly limited, and known aliphatic monocarboxylic acids, alicyclic monocarboxylic acids, and aromatic monocarboxylic acids can be used. From the viewpoint of improving moisture permeability and retention, alicyclic monocarboxylic acids and aromatic monocarboxylic acids are preferably used. As preferable examples of the monocarboxylic acid, the acids shown below can be cited, but the present invention is not limited thereto. As the aliphatic monocarboxylic acid, a fatty acid having 1 to 32 carbon atoms and having a straight chain or a side chain can be preferably used. The number of carbon atoms is more preferably 1-20, even more preferably 1-10. When acetic acid is used, the compatibility with cellulose ester is preferably increased, and a mixture of acetic acid and other monocarboxylic acids is also preferably used.

Preferable aliphatic monocarboxylic acids include saturated fatty acids such as acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, heptanoic acid, caprylic acid, nonanoic acid, capric acid, 2-ethylhexanecarboxylic acid, Undecanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, stearic acid, nonadecanoic acid, eicosanoic acid, behenic acid Alkanoic, lignoceric, cerotic, heptacosanoic, montanic, melissic, and laceric acids; and unsaturated fatty acids, e.g., undecylenic, oleic, sorbic, linoleic acid, linolenic acid and arachidonic acid. Each of these monocarboxylic acids may further have one substituent.

Examples of preferred alicyclic monocarboxylic acids include carboxylic acids such as cyclopentane carboxylic acid, cyclohexane-carboxylic acid, cyclooctane carboxylic acid, bicyclononane-carboxylic acid, dicyclodecane Carboxylic acid, norbornene-carboxylic acid and adamantane carboxylic acid, and derivatives of these carboxylic acids. As preferable aromatic monocarboxylic acids, aromatic monocarboxylic acids obtained by introducing an alkyl group into the benzene ring of benzoic acid (for example, benzoic acid and toluic acid), aromatic monocarboxylic acids having two or more benzene rings, Acids (for example, biphenylcarboxylic acid, naphthalene-carboxylic acid, and tetralincarboxylic acid), and derivatives of these carboxylic acids. Benzoic acid is particularly preferred.

(polyol ester)

The molecular weight of the polyol esters used in the present invention is not particularly limited, but its molecular weight is preferably 300-1,500, more preferably 350-750. The molecular weight is preferably larger in view of exudation properties, and smaller in terms of compatibility with cellulose ester.

The carboxylic acid in the polyol esters of the present invention may be a single carboxylic acid, or may be a mixture of two or more carboxylic acids. The OH groups in the polyol may be fully esterified, or a portion of the OH groups may remain as OH groups. It is preferable to have three or more aromatic rings or cycloalkyl rings in the molecule.

Examples of polyol esters used in the present invention are shown below.

The type and amount of polyol ester affect the physical properties of the film, such as moisture permeability, especially exudation performance and adhesion performance, so they are determined from a comprehensive perspective.

The added amount is preferably 3 to 30% by weight, more preferably 5 to 25% by weight, particularly preferably 5 to 20% by weight of the cellulose acylate.

(ultraviolet absorber)

The cellulose acylate film of the present invention contains an ultraviolet absorber in order to improve the light resistance of the film itself, and to prevent damage to polarizers and liquid crystal compounds of image displays and organic EL compounds of image display elements.

From the viewpoint of preventing damage to liquid crystals, it is preferable to use ultraviolet absorbers excellent in absorbing properties of ultraviolet rays with a wavelength of 370 nm or shorter; The absorption of visible rays is as small as possible.

For example, as such compounds, hydroxybenzophenone compounds, benzotriazole compounds, salicylate compounds, benzophenone compounds, cyanoacrylate compounds, and nickel complex compounds are cited, but the present invention does not limited to this.

Specific examples of the ultraviolet absorber are listed below, but the present invention is not limited to these compounds.

2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzotriazole, 2- (2'-Hydroxy-3'-tert-butyl-5Y-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5- Chlorobenzotriazole, 2-[2′-Hydroxy-3′-(3″, 4″, 5″, 6″-tetrahydrophthalimidomethyl)-5′-methylphenyl ]benzotriazole, 2,2-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl)phenol], 2-(2'-Hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2,4-dihydroxybenzophenone, 2,2'-dihydroxy -4-methoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis(2-methoxy-4-hydroxy-5-benzoylphenylmethane ), 2,4-bis-(n-octylthio)-6-(4-hydroxy-3,5-di-tert-butylanilino)-1,3,5-triazine, 2-(2′- Hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-pentylphenyl)-5-chlorobenzene Triazole, 2,6-di-tert-butyl-p-cresol, pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], triethylene glycol di[3 -(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl base) propionate], 2,4-di(n-octylthio)-6-(4-hydroxy-3,5-di-tert-butylanilino)-1,3,5-triazine, 2-( 2'-Hydroxy-4'-hexyloxyphenyl)-4,6-diphenyltriazine, 2,2-thio-diethylene-bis[3-(3,5-di-tert-butyl -4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, N,N'-hexylidene-bis(3 , 5-di-tert-butyl-4-hydroxy-hydrocinnamamide), 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl) Benzene, tris(3,5-di-tert-butyl-4-hydroxybenzyl)-isocyanurate, phenyl salicylate, p-tert-butyl salicylate, 2,4-dihydroxybenzophenone , 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis(2-methoxy-4-hydroxy- 5-Benzoylphenylmethane-2′-ethylhexyl-2-cyano-3,3-diphenylacrylate and ethyl-2-cyano-3-(3′,4′-methylene Dioxyphenyl)-2-acrylate.

In addition, ultraviolet absorbers disclosed in JP-A-6-148430 can also be preferably used.

It is also possible to use N,N'-bis-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine and other hydrazine-based metal deactivators, and tris(2,4-di Phosphorus-based processing stabilizers such as tert-butylphenyl) phosphite.

These stabilizing compounds are added in an amount of preferably 0.0001 to 1.0 part by weight, more preferably 0.001 to 0.1 part by weight, based on 100 parts by weight of the cellulose acylate.

The ultraviolet absorbent of the present invention preferably has a light transmittance at a wavelength of 370 nm of 20% or less, preferably 10% or less, more preferably 5% or less.

The ultraviolet absorbers can be used in combination of two or more. The ultraviolet absorber may be added to the coating dope in the form of a solution dissolved in an organic solvent such as alcohol, methylene chloride, or dioxane, or may be directly added to the coating dope. The organic solvent-insoluble inorganic powder is dispersed in the organic solvent and cellulose ester with a dissolver or a sand mill, and then added to the coating dope.

In the present invention, the ultraviolet absorber is added in an amount of 0.1-15 parts by weight, preferably 0.5-10 parts by weight, more preferably 0.8-7 parts by weight, based on 100 parts by weight of cellulose acylate.

As the ultraviolet absorber of the present invention, it is also preferable to use an ultraviolet absorbing polymer having little side effects such as adhesion failure due to precipitation and increase in haze value. They are copolymers of ultraviolet absorbing monomers and ethylenically unsaturated monomers having a molar absorptivity of 4,000 or more at a wavelength of 380 nm. From the viewpoint that their own precipitation is small, ultraviolet absorbing copolymers having a weight average molecular weight of 2,000 to 20,000 are preferable.

When the molar absorptivity at a wavelength of 380nm is 4,000 or more, ultraviolet absorption performance is good and sufficient effect of shielding ultraviolet rays can be obtained, so the optical film itself is not colored yellow and the transparency of the optical film increases.

As the ultraviolet absorbing monomer for the ultraviolet absorbing copolymer, it is preferable to use an ultraviolet absorbing monomer having a molar absorptivity at a wavelength of 380 nm of 4,000 or more, preferably 8,000 or more, more preferably 10,000 or more. When the molar absorptivity at a wavelength of 380nm is less than 4,000, a large amount of additives is required to obtain the desired UV absorption performance, which leads to increased haze, decreased transparency, and a large tendency to decrease film strength due to precipitation of the UV absorber.

As a UV-absorbing monomer used in UV-absorbing copolymers, it is necessary that the ratio of the molar absorptivity at 400 nm to the molar absorptivity at 380 nm is 20 or more, and when the ratio is less than 20, the coloring of the film is large, which is not suitable Used as an optical film.

That is, in order to obtain desired ultraviolet absorbing performance by suppressing absorption of light near 400 nm near the visible region, the present invention preferably uses an ultraviolet absorbing monomer having high ultraviolet absorbing performance.

a. UV absorbing monomer

As the ultraviolet absorbing monomer, there are known salicylic acid ultraviolet absorbers (phenyl salicylate, p-tert-butyl salicylate, etc.), benzophenone ultraviolet absorbers (2,4-dihydroxybenzophenone , 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, etc.), benzotriazole UV absorber (2-(2'-hydroxy-3'-tert-butyl-5' -methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2 '-Hydroxy-3',5'-di-tert-amylphenyl)benzotriazole, etc.), cyanoacrylate UV absorber (2'-ethylhexyl-2-cyano-3,3-di Phenylacrylate, ethyl-2-cyano-3-(3′,4′-methylenedioxyphenyl)acrylate, etc.), triazine UV absorber (2-(2′-hydroxy- 4'-hexyloxyphenyl)-4,6-diphenyltriazine, etc.) and compounds disclosed in JP-A-58-185677 and JP-A-59-149350.

As the ultraviolet absorbing monomer of the present invention, it is preferable to randomly select the basic skeleton from the above-mentioned various known ultraviolet absorbers, introduce a substituent containing an ethylenically unsaturated bond, thereby making a polymerizable compound, and select a wavelength of 380 nm Compounds with lower molar absorptivity of 4,000 or greater were used. As the ultraviolet absorbing monomer of the present invention, a benzotriazole compound is preferably used for storage stability.

A particularly preferred ultraviolet absorbing monomer is represented by the following formula (b):

Wherein R ₁₁ represents a halogen atom, or a group substituted by an oxygen atom, nitrogen atom or sulfur atom on the benzene ring; R ₁₂ represents a hydrogen atom, an aliphatic group, an aromatic group or a heterocyclic group; R ₁₃ , R ₁₅ and R ₁₆ each represent a hydrogen atom, an aliphatic group, an aromatic group or a heterocyclic group; R ₁₄ represents a group substituted by an oxygen atom or a nitrogen atom on the benzene ring, provided that R ₁₁ -R ₁₆ at least Any one has a group having the following structure as a partial structure; n represents an integer of 1-4.

Wherein L represents a divalent linking group; _R represents a hydrogen atom or an alkyl group.

Preferred ultraviolet absorbing monomers for use in the present invention are listed below, but the present invention is not limited thereto.

b. Polymer

The ultraviolet absorbing copolymer used in the present invention is preferably a copolymer of the above ultraviolet absorbing monomer and an ethylenically unsaturated monomer, and has a weight average molecular weight of 2,000-20,000, more preferably 7,000-15,000.

When the ultraviolet-absorbing polymer is a homopolymer of an ultraviolet-absorbing monomer, the homopolymer causes a significant increase in haze and a large decrease in transparency, and thus is not suitable for optical film applications. Furthermore, homopolymers of ultraviolet absorbing monomers have low solubility in solvents, and thus are poor in film-forming processability. In the case where the homopolymer has a weight average molecular weight in the above range, its compatibility with the resin is good so that bleeding and coloring to the film surface do not occur even after a lapse of time.

As ethylenically unsaturated monomers which can be copolymerized with ultraviolet absorbing monomers, methacrylic acid and methacrylate derivatives (for example, methyl methacrylate, ethyl methacrylate, propylene methacrylate, etc. ester, butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, octyl methacrylate, cyclohexyl methacrylate, 2-hydroxyethyl methacrylate, 2-methacrylate - Hydroxypropyl, tetrahydrofurfuryl methacrylate, benzyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, etc.), acrylic acid and acrylate derivatives (e.g., Methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, isobutyl acrylate, tert-butyl acrylate, octyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxy-propyl acrylate, Tetrahydrofurfuryl acrylate, 2-ethoxyethyl acrylate, ethoxylated diethylene glycol acrylate, 3-methoxy-butyl acrylate, benzyl acrylate, dimethylaminoethyl acrylate, diethylene glycol acrylate ethyl amino ethyl ester, etc.), alkyl vinyl ethers (for example, methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, etc.), alkyl vinyl esters (for example, vinyl formate, vinyl acetate ester, vinyl butyrate, vinyl caproate, vinyl stearate, etc.), acrylonitrile, vinyl chloride, styrene, etc.

Among these ethylenically unsaturated monomers, acrylates and methacrylates having hydroxyl groups or ether linkages (e.g., 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, methacrylic acid Tetrahydrofurfuryl Acrylate, 2-Hydroxyethyl Acrylate, 2-Hydroxypropyl Acrylate, Tetrahydrofurfuryl Acrylate, 2-Ethoxyethyl Acrylate, Ethoxylated Diethylene Glycol Acrylate, and Acrylate-3 -methoxybutyl ester). These ethylenically unsaturated monomers may be used alone, or two or more may be mixed and copolymerized with an ultraviolet absorbing monomer.

By considering the compatibility of the obtained UV-absorbing copolymer with the transparent resin, the transparency and mechanical strength of the optical film, the desired UV-absorbing properties, the amount of copolymer added, the increase in haze, and the solubility of the copolymer in solvents, The ratio of the amount of ethylenically unsaturated monomer that can be copolymerized with the ultraviolet absorbing monomer is selected. The two are preferably mixed so that 20 to 70% by weight, more preferably 30 to 60% by weight of the ultraviolet absorbing monomer is added to the ultraviolet absorbing copolymer.

The ultraviolet absorbing copolymer of the present invention can be polymerized according to known methods, for example, radical polymerization, anionic polymerization, and cationic polymerization are exemplified. Examples of the polymerization initiator for radical polymerization include azo compounds and peroxides. In particular, azobisisobutyronitrile (AIBN), azobisisobutyrate diester derivatives and benzoyl peroxide are cited. The polymerization solvent is not particularly limited, for example, aromatic hydrocarbon solvents (for example, toluene and chlorobenzene), halogenated hydrocarbon solvents (for example, dichloroethane and chloroform), ether solvents (for example, tetrahydrofuran and dioxane), amide solvents (e.g., dimethylformamide), alcohol solvents (e.g., methanol), ester solvents (e.g., methyl acetate and ethyl acetate), ketone solvents (e.g., acetone, cyclohexanone, and methyl ethyl ketone), and aqueous solvents. Solution polymerization for polymerization with a homogeneous system, precipitation polymerization for precipitating the formed polymer, and emulsion polymerization for polymerization in a micellar state can also be used in the present invention by selecting a solvent.

The weight average molecular weight of the ultraviolet absorbing copolymer can be adjusted by a known method. As a method for adjusting the molecular weight, a method of adding a chain transfer agent (for example, carbon tetrachloride, dodecyl mercaptan, octyl thioglycolate, etc.) is exemplified. The polymerization temperature is room temperature to 130°C, preferably 50-100°C.

The ultraviolet absorbing copolymer is preferably mixed with the cellulose acylate in a ratio of 0.01 to 40% by weight, more preferably 0.5 to 10% by weight. At this time, there is no limitation if the haze of the formed optical film is 0.5 or less. The haze of the formed optical film is preferably 0.2 or less. More preferably, the formed optical film has a haze of 0.2 or less and a light transmittance at a wavelength of 380 nm of 10% or less.

When mixing the ultraviolet absorbing copolymer with the transparent resin, other low-molecular-weight compounds, high-molecular-weight compounds, and inorganic compounds may be used together, if necessary. For example, an ultraviolet absorbing copolymer and other low-molecular-weight ultraviolet absorbers may be mixed with the transparent resin at the same time, and similarly, additives such as antioxidants, plasticizers, and flame retardants are preferably mixed at the same time.

(other additives)

In addition, it is suitable for various uses (e.g., prevention of deterioration (e.g., antioxidant, peroxide decomposer, radical inhibitor, metal deactivator, acid trap, amine), optical anisotropy control agent, film release agent, antistatic agent, infrared absorber, etc.) can be added to the cellulose acylate composition of the present invention in various production processes, and these additives can be solid or oily substances. That is, melting point and boiling point are not particularly limited. Also, compounds disclosed in JP-A-2001-194522 are used as infrared absorbing dyes.

These additives can be added at any time and place in the coating dope preparation process, but a new process of adding additives can be provided as the last step process in the coating dope preparation process. The amount of each compound added is not particularly limited as long as the respective functions can be exhibited. When the cellulose acylate film includes multiple layers, the types and amounts of additives may vary in each layer, and as disclosed in JP-A-2001-151902, which is a conventionally known process. This method is described in detail in Hatsumei Kyokai Kokai Giho, Kogi No. 2001-1745 (published by Hatsumei Kyokai, March 15, 2001), pp. 16-22, and the materials described therein are preferably used. The addition amount of each additive is arbitrarily selected within the range of 0.002 to 20% by weight based on the weight of the total components of the cellulose acylate.

(Method for producing cellulose acylate film)

The cellulose acylate film used as the support in the present invention is preferably produced by a solvent casting method. In the solvent casting method, a cellulose acylate film is prepared using a solution (coating dope) obtained by dissolving cellulose acylate or the like in an organic solvent.

(Preparation method of coating dope)

As the solvent used in the solvent casting method, organic solvents commonly used in the solvent casting method can be used without limitation, for example, solvents having a solubility parameter of 17-22 are preferable. Specifically, lower aliphatic hydrocarbon chlorides, lower aliphatic alcohols, ketones having 3-12 carbon atoms, esters having 3-12 carbon atoms, Ethers, aliphatic hydrocarbons having 5-8 carbon atoms, and aromatic hydrocarbons having 6-12 carbon atoms.

Ethers, ketones and esters may have a ring structure. A compound having two or more functional groups of any of ethers, ketones and esters (ie, -O-, -CO- and -COO-) can also be used as the organic solvent. Also, the organic solvent may have other functional groups, for example, alcoholic hydroxyl groups. When the organic solvent has two or more functional groups, the number of carbon atoms will be within the above preferred range of the number of carbon atoms of the compound having any functional group.

Specifically, the compounds described in the above Kogi No. 2001-1745, pp. 12-16 are exemplified.

In the present invention, as the organic solvent, it is preferable to use a mixed solvent of two or more organic solvents, and it is particularly preferable to use an organic solvent of a mixture of three or more solvents different from each other, wherein the first solvent is an organic solvent having 3 or more Ketones with 4 carbon atoms or esters with 3 or 4 carbon atoms or mixtures thereof, the second solvent is selected from ketones and acetoacetates with 5-7 carbon atoms, and the third solvent is selected from the group with a boiling point of 30-170°C Alcohols and hydrocarbons with a boiling point of 30-170°C.

Specifically, from the viewpoint of the solubility of cellulose acylate, it is preferable to use a mixed solvent containing acetates, ketones, and alcohols in a mixing ratio of 20-90% by weight of acetates, 5-60% by weight of ketones. Classes and 5-30% by weight of alcohols.

In this mixed solvent, the mixing ratio of alcohols in the entire solvent is preferably 2-40% by volume, more preferably 3-30% by volume, even more preferably 5-20% by volume.

Among alcohols, monohydric or dihydric alcohols having 1 to 8 carbon atoms, and fluoroalcohols having 2 to 10 carbon atoms are preferable, and methanol, ethanol, and 1-propanol are listed as more preferable alcohols , 2-propanol, 1-butanol, 2-butanol, tert-butanol, 1-pentanol, 2-methyl-2-butanol, cyclohexanol, ethylene glycol, 2-fluoroethanol, 2, 2,2-trifluoroethanol and 2,2,3,3-tetrafluoro-1-propanol. These alcohols may be used alone or in combination of two or more.

It is preferable to use a non-halogenated organic solvent containing no halogenated hydrocarbon, especially a substantially non-chlorinated solvent containing no chlorine atoms (hereinafter referred to simply as "non-chlorinated solvent").

Halogenated hydrocarbons, for example, dichloromethane, can be used technically without problems, but an organic solvent substantially free of halogenated hydrocarbons is preferable from the viewpoint of global environment and working environment. "Essentially free" means that the proportion of halogenated hydrocarbons in the organic solvent is less than 5% by weight (preferably less than 2% by weight). It is preferable that halogenated hydrocarbons, such as methylene chloride, are not detected at all from the produced cellulose acylate film.

As examples of the non-chlorinated solvent used in the present invention, those disclosed in paragraphs [0021] to [0025] of JP-A-2002-146043 and paragraphs [0016] to [0021] of JP-A-2002-146045 are cited. solvent.

As the non-chlorinated solvent, a mixed solvent containing at least one organic solvent selected from ethers, ketones and esters having 3 to 12 carbon atoms, and alcohols, wherein the alcohol content is 2 to 40% by weight, is preferred.

The above mixed solvent may contain aromatic or aliphatic hydrocarbons having 5-10 carbon atoms in an amount of 0-10% by volume. Examples of the hydrocarbons include cyclohexane, hexane, benzene, toluene and xylene.

In order to increase the transparency of the film or improve the solubility, in addition to the above organic solvent, it is preferable to add 10% by weight or less of fluoroalcohol to the coating dope based on the total amount of the organic solvent. As such fluoroalcohols, compounds disclosed in paragraph [0020] of JP-A-8-143709 and paragraph [0037] of JP-A-11-60807 are exemplified. These fluoroalcohols may be used alone or in combination of two or more.

In preparing the coating dope of the present invention, the reaction vessel may be filled with an inert gas such as nitrogen.

Furthermore, the viscosity of the coating dope immediately before film formation is sufficient to be castable, and the viscosity is generally preferably 10-2,000 ps·s, particularly preferably 30-400 ps·s.

As for the preparation method of the coating dope, the dissolution method is not particularly limited, and the dissolution may be performed by any method of room temperature dissolution, cooling dissolution, high temperature dissolution, or a combination of these methods. The preparation method of coating dope is disclosed in JP-A-5-163301, JP-A-61-106628, JP-A-58-127737, JP-A-9-95544, JP-A-10-95854, JP-A- -A-10-45950, JP-A-2000-53784, JP-A-11-322946, JP-A-11-322947, JP-A-2-276830, JP-A-2000-273239, JP-A -11-71463, JP-A-4-259511, JP-A-2000-273184, JP-A-11-323017 and JP-A-11-302388. The process of dissolving the polymer of the support material in an organic solvent disclosed in the above patents can be freely used in the present invention. When cellulose acylate is used as a polymer, the coating solution of cellulose acylate is often concentrated and filtered. These details are described above on page 25 of Kogi No. 2001-1745. When the dissolution is carried out at high temperature, in almost all cases the dissolution temperature is higher than the boiling point of the organic solvent used so that the organic solvent is used under pressure.

The above plasticizer, fine particles and necessary other additives such as (retardation adjuster and ultraviolet absorber) are added to the coating dope.

(How to add and mix fine particles)

When fine particles are added to cellulose acylate, it is important that there are no coarse particles and that the particles are stably dispersed so as not to cause flocculation and sedimentation. When these conditions are satisfied, the method is not particularly limited and the desired cellulose acylate coating dope can be obtained. A method of preparing a dispersion of fine particles different from the preparation of the coating dope and mixing the dispersion with the coating dope is a preferred method.

Additives other than fine particles, for example, may be added when cellulose acylate is mixed with a solvent, or may be added after preparing a mixed solution of cellulose acylate and solvent. Also, the fine particles can be added and mixed immediately before casting the dope by in-line screw type mixing. These additives may be added directly, but it is preferable to dissolve them in a solvent or binder (preferably cellulose acylate) in advance, or they may be dispersed and used as a stabilizing solution as the case may be.

(film formation method)

The method of producing a film using a coating dope is described below. As a method and apparatus for producing a cellulose acylate film, known solvent casting methods and solvent casting film forming apparatuses called drum methods and belt methods are used.

The prepared coating dope (cellulose acylate solution), which was previously stored in a storage container, was taken out from the dissolver (dissolving tank), and the foam in the coating dope was defoamed, as final preparation process. It is important to remove agglomerates and impurities from the coating dope produced by precise filtration. In particular, it is preferable to use a filter having as small a pore diameter as possible within a range not to remove components in the coating dope. When filtering, use a filter with an absolute filtration accuracy of 0.1-100 μm, more preferably 0.1-25 μm. The thickness of the filter is preferably 0.1-10 mm, more preferably 0.2-2 mm. In this case, the filtration pressure is preferably 15 kgf/cm ² or less, more preferably 10 kgf/cm ² or less, even more preferably 2 kgf/cm ² or less.

For precise filtration, it is preferred to undergo multiple filtrations to gradually reduce the pore size.

The type of filter for precise filtration is not particularly limited as long as the filter has the above properties, for example, a filament type, a felt type, and a mesh type are exemplified. The material of the filter for precise filtration is not particularly limited as long as the filter has the above properties and has no adverse effect on the coating liquid, for example, stainless steel, polyethylene, polypropylene and nylon are exemplified.

By means of a pressure-type quantitatively determined gear pump capable of accurately adding a prescribed amount of solution feed, for example, by the number of revolutions, the prepared coating dope is transferred from the discharge port to the compression die, and the coating dope is transferred from the compression die The slit was uniformly cast onto the metal support of the continuously running casting section, and the wet-dry coating dope film (web) was peeled off from the metal support at the almost circular peeling point of the metal support. Both ends of the obtained web are clamped with clips, and the web is transferred by a tenter while maintaining the width of the web, dried, transferred by a roller of a drying device to complete drying, and wound up to a predetermined length by a winder. The combination of the tenter frame and the rolls of the drying device varies depending on the purpose.

The surface of the metal support used in the casting process preferably has an arithmetic average roughness value (Ra) of 0.015 μm or less, a ten-point average roughness (Rz) of 0.05 μm or less, more preferably an arithmetic average roughness value ( Ra) is 0.001-0.01 μm, ten-point average roughness (Rz) is 0.001-0.02 μm or less. More preferably the ratio (Ra)/(Rz) is 0.15 or greater. By the specified surface roughness of the metal support, the mesh can be easily and uniformly peeled off from the metal support, and the surface configuration of the thin film after film formation can be controlled within the scope of the present invention.

Each of the processes (casting (including co-casting), drying, peeling and stretching) described in detail on pages 25 to 30 of the above Kogi No. 2001-1745 can be preferably used. In the casting process, one coating dope may be cast by single-layer casting, or two or more coating dopes obtained by dissolving different types of polymers may be simultaneously and/or continuously co-cast.

In the process of film formation from the coating dope containing the above composition, the drying process is important for film formation without agglomeration and partial presence of the compound added.

The coating dope on the support is usually dried by various methods, for example, the method of applying hot air to the support from the front side of the support (drum or belt), that is, the front side of the omentum on the support ; a method of applying hot air to a support from the back side of a drum or belt; and contacting a temperature control liquid with the drum or belt from the opposite side of the casting surface to heat the drum or belt via heat transfer, thereby controlling the surface temperature The liquid heat transfer method, and the liquid heat transfer method is preferably used. The temperature of the surface of the support before casting may be any degree as long as the temperature is lower than the boiling point of the solvent used for coating the dope. However, the temperature is preferably 1 to 10°C lower than the boiling point of the solvent having the lowest boiling point in order to speed up drying, or in order to make the coating dope on the support lose fluidity.

The drying temperature in the drying process of the cellulose acylate film obtained by drying the tape-cast coating dope cast is 5 to 250°C, particularly preferably 20 to 180°C. In order to further remove residual solvent, the film is dried at 30-160° C. Preferably the temperature is gradually increased to evaporate residual solvent. This method is disclosed in JP-B-5-17844. The time required from casting to peeling can be shortened by this method. Depending on the solvent used, the drying temperature, the amount of drying air and the drying time are changed, and thus these conditions are preferably selected arbitrarily according to the type and combination of the solvents used.

In order to obtain a film excellent in dimensional stability, the residual amount of solvent in the finished film is 2% by weight or less, preferably 0.4% by weight or less. In the present invention, by using a release agent, the peeling time can be shortened, and since the resistance at the time of peeling is reduced, surface properties can be obtained (caused by unevenness in the width direction at the time of peeling and gel-like lumps left after peeling) protrusions) undamaged cellulose acylate film.

In particular, the average drying speed from casting of the coating dope to peeling is preferably greater than 300% by weight/min and 1000% by weight/min or less in consideration of maintaining good productivity and suppressing the occurrence of lack of air uniformity, More preferably greater than 400 wt%/min and 900 wt%/min or less, most preferably greater than 500 wt%/min and 800 wt%/min or less.

The average drying speed is a value obtained by dividing the change in solvent content in the cast coating dope by time.

The average drying speed can be adjusted freely by adjusting the temperature of the drying air, the amount of air, the concentration of solvent gas, the surface temperature of the casting support, the temperature of the coating dope to be cast, and the wet thickness of the coating dope to be cast. and the solvent composition of the coating dope to be cast.

(peeling process)

The peeling process is a process of peeling off the omentum in which the solvent has evaporated at the peeling position. Transfer the stripped omentum to the next step. When the residual amount of the solvent at the exfoliation point (the following equation) is too large, it is difficult to exfoliate; and when the omentum is too dry on the support, partial omentum is incompletely exfoliated. In order to increase the film-forming speed (since the omentum is peeled off while leaving the residual solvent as much as possible, the film-forming speed can be increased), a gel casting method is known. The method includes a method of adding a poor solvent of cellulose ester during preparation of a coating solution and performing gelation after coating dope casting, and a method of gelling by lowering the temperature of the metal support. By gelling on the support, the strength of the film at the time of peeling is increased, the peeling can be accelerated and the film formation time can be shortened. The solvent residual amount of the omentum after peeling can be determined by the length of the metal support.

Preferably, the omentum is peeled when the solvent residual amount at the peeling position is 5-150% by weight, more preferably 10-120% by weight. In the case of peeling the web while leaving a large amount of residual solvent, if the web is too soft the flatness suffers, and pinching and streaks tend to occur due to peeling tension.

The residual amount of solvent after stripping can be represented by the following equation.

Amount of residual solvent (weight%) = {(M-N)/N}×100

Where M is the weight of the omentum at any point, and N is the weight of the omentum with the weight M after drying at 110° C. for 3 hours.

In the drying process after peeling off the web from the support, the film tends to shrink in the width direction due to evaporation of the solvent. The longer the drying time, the greater the shrinkage. Drying is preferably performed by controlling shrinkage as much as possible to obtain a finished film with good flatness. Thus, a drying method in which both ends of the web are held with clips while maintaining the width of the web throughout the drying process of the partial pass (tenter system) is preferred, as disclosed in JP-A-62-46625.

(drying and stretching process)

Generally speaking, after peeling, a drier that alternately passes and transfers the web on rollers arranged in a zigzag, a tenter that transfers the web by clamping both ends of the web, or both , to dry the omentum. Blowing hot air against both sides of the web is a conventional drying method, but heating with microwaves instead of hot air can also be used. Rapid drying tends to destroy the flatness of the finished film. Throughout the process, the drying temperature is usually 40-250°C, preferably 40-180°C. Depending on the solvent used, the drying temperature, the amount of drying air, and the drying time are changed, whereby the drying conditions are preferably selected arbitrarily according to the type and combination of the solvents used.

Drying is preferably carried out under such conditions that the amount of residual solvent in the finished cellulose acylate film ends up being 0.01 to 1.5% by weight, more preferably 0.01 to 1.0% by weight.

(stretching process)

In the casting process, it is preferable to perform uniaxial stretching in only one direction of the casting direction (axial direction), or biaxial stretching in the casting direction and the other direction (transverse direction).

The mechanical strength and optical characteristics (retardation value) of the produced cellulose acylate film can be adjusted. The stretch ratio is preferably 3-100%.

By employing the following stretching methods (1) and (2) or both, the flatness, film strength, and optical properties of the film can be adjusted within prescribed ranges.

(1) Stretching is performed at a stretch ratio of 3-40%, preferably 7-38%, more preferably 15-35% in the transverse direction. Next, it is treated at 20-160° C. while stretching in the axial direction at a ratio of 0.4%-5%, preferably 0.7%-4%, more preferably 1%-3.5%.

(2) During stretching, a temperature difference is imparted between the obverse and reverse surfaces. The temperature of the surface adhering to the substrate (belt or drum) during casting is made higher by 2-20°C, preferably 3-15°C, more preferably 4-12°C, than the temperature of the opposite surface.

By these methods, the localized presence of additives (plasticizers, ultrafine particles, UV absorbers) is resolved, and the optical properties of the obtained films are homogenized and the mechanical properties are improved.

At the same time, other functional layers (eg, adhesive layer, dye layer, antistatic layer, antihalation layer, ultraviolet absorbing layer, polarizing sheet, etc.) can be cast.

As described above, in the present invention, it is preferable that the support is a cellulose acylate film, and the cellulose acylate film is prepared from a fiber A film-forming process of forming a cellulose acylate film from an acylate solution, and a stretching process of stretching a cellulose acylate film.

In order to make the film thickness fluctuation of the cellulose acylate film not more than ±3%, it is effective to (1) adjust the solution (coating dope) obtained by dissolving the cellulose acylate film in the organic solvent at the time of casting The concentration and viscosity of the film, and (2) adjust the drying temperature of the film surface, the amount of air when using dry air, and the direction of the air during the drying process.

(Characteristics of Cellulose Acylate Film (Surface Configuration))

A cellulose acylate film preferably used as a support for an antireflection film has a specific surface configuration. The surface configuration of the cellulose acylate film is described below.

According to JIS B0601-1994, the surface of the side of the cellulose acylate film on which the antireflection film is provided has an arithmetic average roughness value (Ra) of the surface roughness of the film of 0.0005-0.1 μm, a value of ten of 0.001-0.3 μm Point average roughness (Rz) and maximum height (Ry) of 0.5 μm or less, preferably (Ra) 0.0002-0.05 μm, (Rz) 0.005-0.1 μm, (Ry) 0.3 μm or less, especially It is preferable that (Ra) is 0.001-0.02 μm, (Rz) is 0.002-0.05 μm, and (Ry) is 0.1 μm or less.

Within the above range, an antireflection film having no coating unevenness, having uniform coating properties, and good adhesion between the support and the coating film can be provided.

Also, in the surface configuration of minute unevenness, it is preferable that the ratio of the arithmetic average roughness (Ra) to the ten-point average roughness (Rz), (Ra/Rz) is 0.1 or more, and the average of the surface roughness of the film The distance (Sm) is 2 μm or less. Here, the relationship between Ra and Rz shows the uniformity of surface roughness. More preferably, the ratio (Ra/Rz) is 0.15 or more, and the average distance (Sm) is 1-0.1 μm, especially preferably the ratio (Ra/Rz) is 0.2 or more, and the average distance (Sm) is 0.1-0.001 μm .

The profile of surface roughness can be evaluated with transmission electron microscopy (TEM) and atomic force microscopy (AFM).

From the viewpoint of reducing visible defects and improving yield, it is preferable that the number of optical defects having a visible size of 100 μm or more in the cellulose acylate film is 1 or less/m ² .

The optical defects can be observed with a polarizing microscope under crossed Nicols by placing the lag axis of the film parallel to the absorption axis of the polarizer. Defects that appear to be bright are roughly circular areas, and the number of bright areas with a diameter of 100 μm or more is counted. Brightness regions having a diameter of 100 µm or more can be easily observed with the naked eye.

That is, according to JIS B0601-1994, the cellulose acylate film has an arithmetic average roughness value (Ra) of the surface roughness of the film of 0.0005-0.1 μm, a ten-point average roughness (Rz) of 0.001-0.3 μm, and 2 μm or smaller film surface roughness mean distance (Sm). Also, it is preferable that the number of optical defects having a visible size of 100 μm or more in the cellulose acylate film is 1 or less/m ² .

(Optical properties of thin films)

The cellulose acylate film preferably has a light transmittance of 90% or more and a haze value of 1% or less, more preferably a light transmittance of 92% or more and a haze value of 0-0.5%.

The haze value can be measured with a haze meter (MODEL 1001DP, manufactured by Nippon Denshoku Industries Co., Ltd.; HR-100, manufactured by Murakami Color Research Laboratory) in accordance with JIS-K-7105.

(Dynamic properties of thin films)

(tear strength)

Even at the preceding film thickness, it is preferable that the cellulose acylate film has a tear strength of 2 g or more based on the tear test method (Elmendorf tear method) of JIS K7128-2:1998 from the viewpoint of being able to sufficiently maintain the film strength , more preferably 5-25g, even more preferably 6-25g. The film thickness is 60 µm, and the value is preferably 8 g or more, more preferably 8 to 15 g.

Specifically, a sample piece of 50 mm x 64 mm was subjected to humidity conditioning at 25° C. and 65% RH for 2 hours, and then the tear strength was measured with a lightweight tear strength tester.

(scratch resistance)

The scratch resistance is preferably 2 g or more, more preferably 5 g or more, and especially preferably 10 g or more. Within this range of scratch resistance, the scratch resistance and processability of the film surface can be maintained without problems.

Scratch resistance can be evaluated in terms of load (g) by scratching the surface of the support with a gemstone stylus having a cone with an apex angle of 90° and a tip radius of 0.25 m, and scratches that can be observed with the naked eye.

(residual solvent content of film)

Rolling can be prevented by controlling the residual solvent amount of the support used in the present invention to 0-1.5%, more preferably 0.1-0%.

This may be due to the fact that the reduction of the free volume due to the reduction of the amount of residual solvent in film formation by solvent casting method is the main factor.

Specifically, drying is preferably performed so that the residual solvent amount of the cellulose acylate film becomes 0.01 to 1.5% by weight, more preferably 0.01 to 1.0% by weight.

(Vapor permeability and moisture content of the film)

Based on the method described in JIS Z0208 (25°C, 90%RH), it is preferable that the moisture permeability of the cellulose acylate film is in the above range, whereby the adhesion failure of the antireflection film can be reduced, and when the film is used as an optical Protective films for compensating lenses and polarizers do not cause hue fluctuations and angle reductions in visibility when installed in liquid crystal displays.

Moisture permeability can be measured according to Kobunshi no Bussei II (Physical Properties of Polymers II) (Kobunshi Jikken Koza 4, Kyoritsu Publishing Co.), pp. 285-294, amount of vapor permeation (gravimetric method, thermometer method, vapor pressure method) determined by the method described in.

Regardless of the film thickness, it is preferable that the moisture content of the cellulose acylate film at 30° C. 85% RH is 0.3 to 12 g/m ² , more preferably 0.5 g/m 2 , in order not to lower the adhesiveness with water-soluble polymers such as polyvinyl alcohol. -5 g/m ² . When the moisture content is more than 12 g/m ² , the dependence of retardation on moisture fluctuation also becomes large, and it is not preferable.

Various additives can be added to the transparent support in order to adjust the mechanical properties (film strength, roll-up, dimensional stability, sliding properties) and durability (moisture and heat resistance, weather resistance) of the film. For example, plasticizers (such as phosphoric acid esters, phthalic acid esters, esters of oily alcohols and fatty acids), ultraviolet inhibitors (such as hydroxybenzophenone compounds, benzotriazole compounds, Salicylate compound, cyanoacrylate compound), deterioration preventive agent (for example, antioxidant, peroxide decomposer, free radical inhibitor, metal deactivator, acid scavenger, amine), fine particles (for example, SiO ₂ , Al ₂ O ₃ , TiO ₂ , BaSO ₄ , CaCO ₃ , MgCO ₃ , talc, kaolin), release agent, antistatic agent and infrared absorber. They are described in detail in Hatsumei Kyokai Kokai Giho, Kogi No. 2001-1745 (published by Hatsumei Kyoka, March 15, 2001), pp. 17-22.

The additive is added in an amount of preferably 0.01-20% by weight of the transparent support, more preferably 0.05-10% by weight.

Transparent substrates can be surface treated. Examples of surface treatment include chemical treatment, mechanical treatment, corona discharge treatment, flame treatment, ultraviolet treatment, high frequency treatment, glow discharge treatment, reactive plasma treatment, laser treatment, mixed acid treatment, and ozone oxidation treatment. In particular, Hatsumei Kyokai Kokai Giho Kogi No. 2001-1745 (published on March 15, 2001), pages 30 and 31, and JP-A-2001-9973 are cited. Preferred surface treatments are glow discharge treatment, ultraviolet treatment, corona discharge treatment and flame treatment, more preferred treatments are glow discharge treatment and ultraviolet treatment.

<Formation method of anti-reflection film>

The antireflection film of the present invention can be formed by the following method, but the present invention is not limited thereto. The forming method is described with reference to the third embodiment.

(Preparation of Coating Solution)

First, a coating liquid containing components forming each layer is prepared. At this time, by suppressing the volatile matter content in the solvent to a minimum, the moisture content in the coating can be prevented from rising. The moisture content in the coating is preferably 5% or less, more preferably 2% or less. Suppression of the volatile matter content in the solvent can be achieved by improving the seal of the tank while stirring after adding each material, and minimizing the contact area of the coating liquid with air during the operation of moving the liquid. A means of reducing the moisture content of the coating solution can be provided during, before and after coating.

Corresponding to the dry film thickness (about 50nm-120nm) of the layer that is directly coated on the light scattering layer and the hard coat layer (low refractive index layer, medium refractive index layer), it is preferable to form the light scattering layer and the hard coat layer. A filter capable of removing nearly all (90% or greater) impurities is provided in the layer. Since the particle size of the translucent particles providing light-diffusing properties is the same as or larger than the film thickness of the low-refractive index layer and the medium-refractive index layer, it is preferable to filter the intermediate solution to which all materials except the translucent particles are added . When an upper filter capable of filtering out impurities having a small particle size cannot be obtained, it is preferable to perform filtration capable of removing at least almost all impurities corresponding to the wet film thickness (1-10 μm or so) of the layer directly provided thereon. In this way, defects in layers formed directly above can be reduced.

(coating, drying and curing)

Next, the coating solution of a layer formed directly on the support, such as a light scattering layer or a hard coat layer, is coated by dip coating, air knife coating, curtain coating, roll coating, wire rod coating, gravure coating, etc. Cloth, microgravure coating, or extrusion coating onto a transparent support (see US Pat. No. 2,681,294), followed by heating and drying. Thereafter, the coating is hardened by at least one of light irradiation and heating, thereby forming a light-scattering layer or a hard coat layer.

Coating and curing of a smooth light-scattering layer can be performed by multilayering the structure of the light-scattering layer, if necessary, and before coating the light-scattering layer.

Next, a low-refractive-index coating layer is coated on the light-scattering layer in a similar manner, and the coating is hardened by at least one of light irradiation and heating, whereby the antireflection film of the present invention is obtained.

When forming the light-scattering layer, it is preferable to apply the coating liquid directly on the base film at a wet film thickness of 1 to 20 μm, or to apply via other arbitrary layers. Also, when forming the low-refractive index layer, it is preferable to coat the coating liquid on the light-scattering layer with a wet film thickness of 2 to 5 μm. .

The light-scattering layer and the low-refractive-index layer are directly coated onto the base film or coated onto the base film through other arbitrary layers, and then transferred to a heating zone in the form of a web to dry the solvent. The temperature of the drying zone is preferably 25 to 140° C., and the temperature of the drying zone in the first half is preferably relatively low, and the temperature in the second half is preferably relatively high, provided that the temperature is preferably lower than that of each coating liquid composition except for the solvent. The temperature at which the contained components begin to volatilize. For example, among commercially available products in which a photoradical generator is mixed with an ultraviolet curable resin, some products volatilize several 10% in a few minutes in hot air at 120°C, and some products evaporate in hot air at 100°C Volatilization takes place in several monofunctional and difunctional acrylate monomers. In this case, the drying temperature is preferably lower than the temperature at which components contained in the coating liquid other than the solvent start to volatilize.

Also, it is preferable that after each coating liquid is coated on the base film, the air velocity of the drying air is 0.1-2 m/sec, and the solid concentration of the coating liquid is 1-50% to prevent drying unevenness.

After each coating liquid is coated on the base film, in order to prevent uneven drying due to heat transfer of the transfer roll, the temperature difference between the transfer roll and the base film in contact with the surface of the web opposite to the coating surface Preferably it is 0-20°C.

After the solvent dries, the coating is hardened by passing the omentum through areas of the omentum that are arbitrarily irradiated with ionizing radiation and heated to harden each layer of the omentum. When the coating layer is an ultraviolet curable resin, it is preferable that each layer is hardened by radiation receiving ultraviolet rays at a radiation dose of 10 to 1,000 mJ/cm ² . At this time, the distribution of the irradiation dose in the lateral direction of the omentum including both ends is preferably 50-100%, more preferably 80-100%, of the maximum irradiation dose at the central portion. When nitrogen flushing is required to lower the oxygen concentration to accelerate surface curing, the oxygen concentration is preferably 0.01-5%, and the distribution of the lateral oxygen concentration is preferably 2% or less. The curing conditions of the low refractive index layer are as described above.

In the case where the curing speed (100-residual functional group content) of the light-scattering layer reaches a certain value less than 100%, when the low-refractive-index layer is provided thereon and the low-refractive-index layer is irradiated with ionizing radiation and heated in any manner When hardened, if the curing speed of the light scattering layer is higher than that before coating the lower light scattering layer, the adhesion between the light scattering layer and the low refractive index layer is improved.

The formation method of the antireflection film usable in the present invention will be described in detail.

The layers of the antireflective film in multilayer configuration can be formed by dip coating, air knife coating, curtain coating, roll coating, die coating, wire rod coating, gravure coating, or extrusion coating (See US Patent 2,681,294). When each layer is coated by a gravure coating method, less coating liquid for each layer of the antireflection film can be uniformly coated and is preferable. Microgravure coating has high film thickness uniformity and is more preferable. Coating by a die coating method is more preferable, and a coating method using a novel die coater described later is especially preferable. Two or more layers can be applied simultaneously. Simultaneous coating is disclosed in US Patents 2,761,791, 2,941,898, 3,508,947, 3,526,528 and Yuji Harasaki, Coating Kogaku, p. 253, Asakura Shoten (1973).

In the antireflection film of the present invention, since at least the low-refractive index layer is laminated, if there are impurities such as dust, defects in light-emitting points are conspicuous. The light-emitting point defect of the present invention is a defect visible to the naked eye by reflection of the coated film, and it can be visually detected by coating the reverse side of the antireflection film after coating in black. Luminous point defects visible to the naked eye are usually 50 μm or larger. When there are many light-emitting point defects, the yield decreases, so that a large-sized antireflection film cannot be produced.

The number of light-emitting point defects in the antireflection film of the present invention is 20/m ² or less, preferably 10 or less, more preferably 5 or less, especially preferably 1 or less.

In order to continuously prepare an antireflection film, a process of continuously feeding a support film rolled into a roll, a process of applying a coating liquid and drying it, a process of drying the coated film, and forming a support having a hardened layer The process of rolling up the body film.

The film support is continuously fed into the clean room from the film support rolled into a roll. In the clean room, the static electricity carried by the film support is destaticized with a destaticizer, and then the impurities on the film support are removed with a dust collector. Next, the coating liquid is coated on the film support with a coating device installed in the clean room, and the coated film support is transported to a drying room and dried.

The film support with the dried coating is transported from the drying chamber to the radiation curing chamber, the film support is irradiated with radiation, and the monomers contained in the coating polymerize and harden. Further, the film support having the hardened layer hardened by irradiation with radiation is sent to a heat curing section and is completely cured by heat, and the film support with the hardened layer which is completely hardened is rolled into a roll.

These processes may be performed every time one layer is formed, or a plurality of coating section-drying room-irradiation curing section-heating curing room may be provided and these processes may be performed continuously, but from the viewpoint of productivity, it is preferable to perform the formation of each layer continuously . An example of equipment for continuously performing coating of each layer is shown in FIG. 2 . The apparatus is equipped with a process 110 of continuously feeding the support film rolled into a roll, a process 120 of winding the support film rolled into a roll, and provides film forming units 100, 200, 300 and 400 between 110 and 120 . The equipment shown in Figure 6 is an example of continuous coating of four layers without winding, and of course the number of film-forming units can be changed according to the layer configuration. The film forming unit 100 includes a process 101 of applying a coating liquid, a process 102 of drying the coating, and a process 103 of curing the coated film.

More preferably, the support film that has been coated with the hard coat layer is continuously sent out by using an apparatus equipped with three film-forming units, in each film-forming unit, a medium-refractive-index layer, a high-refractive-index layer, and a low-refractive-index layer are used. It is coated and rolled into a roll. More preferably, by using an apparatus equipped with four film-forming units as shown in FIG. High index layer and low refractive index layer are coated, and then rolled into a roll.

In order to prepare an antireflective film having fewer light-emitting point defects, precise control of the degree of dispersion of high-refractive-index ultrafine particles contained in a high-refractive-index layer coating liquid, and precise filtration of the coating liquid are exemplified. At the same time, it is preferable that the coating process of the coating part and the drying process of the drying room be carried out in a highly clean air environment, and the dust on the film should be sufficiently removed. Based on the air cleanliness standard of US Standard 209E, the air cleanliness of the coating process and drying process is preferably Class 10 (353 particles/m ³ or less for particles with a particle size of 0.5 μm or larger) or higher , more preferably Class 1 (35.5 particles/m ³ or less for particles with a particle size of 0.5 μm or larger) or higher. It is more preferable that the air cleanliness is also high in feeding and winding sections other than the coating-drying process.

As the dedusting method used in the dedusting process of coating pretreatment, the method disclosed in JP-A-59-150571 to press a nonwoven fabric or blade on the surface of the film, the method disclosed in JP-A-10-309553 to A method of blowing high-purity air against the film to remove dust on the film and sucking the dust through the adjacent suction port, and against the film disclosed in JP-A-7-333613 (new ultra-cleaner, produced by Shinko Co.) A method of blowing compressed air subjected to ultrasonic vibrations to remove adhering substances and suctioning the removed substances.

In addition, a method of adding a film to a washing tank and removing adhering substances by ultrasonic waves, a method of feeding a cleaning liquid to a film, blowing and sucking with high-speed air disclosed in JP-A-49-13020, and JP-A-49-13020 may be used. - The method disclosed in A-2001-38306 of continuously rubbing a film with a roller wetted with a liquid, spraying the liquid on the rubbed surface and cleaning it. Among these dedusting methods, the method of dedusting by ultrasonic waves and the method of dedusting by wetting are particularly preferable in terms of dedusting effect.

Also, before performing the dust removal process, it is particularly preferable to destaticize the static electricity on the film support in view of increasing the dust removal effect and suppressing the adhesion of dust. As for this dust removal method, an ionization source subjected to corona discharge, an ionization source subjected to light radiation such as UV and soft X-rays can be used. The voltage of the film support before dust removal and coating is 1,000 V or less, preferably 300 V or less, particularly preferably 100 V or less.

(dispersion medium for coating)

The dispersion medium for coating is not particularly limited. The dispersion medium may be used alone or in admixture of two or more of the above. Preferred dispersion media are aromatic hydrocarbons, such as toluene, xylene, styrene, etc.; chlorinated aromatic hydrocarbons, such as chlorobenzene, o-dichlorobenzene, etc.; methane derivatives, such as monochloromethane, etc., chlorinated Aliphatic hydrocarbons; chlorinated aliphatic hydrocarbons including ethane derivatives, such as monochloroethane, etc.; alcohols, such as methanol, isopropanol, isobutanol, etc.; esters, such as methyl acetate , ethyl acetate, etc.; ethers, such as diethyl ether, ketones such as 1,4-dioxane, such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.; glycol ether aliphatic hydrocarbons, such as cyclohexane, etc.; aliphatic hydrocarbons, such as n-hexane, etc.; and a mixture of aliphatic or aromatic hydrocarbons. Among these solvents, a dispersion medium for coating containing only ketones or a mixture of two or more kinds of ketones is particularly preferred.

(Physical properties of coating liquid)

Since the possible coating speed of the coating method in the above range of the present invention is greatly influenced by the physical properties of the coating liquid, it is necessary to control the physical properties of the coating liquid, particularly viscosity and surface tension, at the time of coating.

The viscosity is preferably 2.0 [mPa·sec] or less, more preferably 1.5 [mPa·sec] or less, most preferably 1.0 [mPa·sec] or less. The viscosity fluctuates with the shear rate of the coating liquid, so the above values show the viscosity at the shear rate at the time of coating. When a thixotropic agent is added to the coating liquid, high shear is applied during coating to lower the viscosity, and no shear is applied during drying to increase the viscosity, so unevenness during coating hardly occurs and is preferable.

Although the amount of the coating liquid coated on the transparent support is not a physical property, it also affects the possible coating speed in the above range. The amount of the coating liquid coated on the transparent support is preferably 2.0 to 5.0 ml/m ² . When the amount of the coating liquid coated on the transparent support increases, the possible coating speed of the above range increases and is preferable, but if the amount of the coating liquid coated on the transparent support increases too much, use Since the load on drying increases, it is preferable to determine the amount of the coating liquid to be coated on the transparent support based on the specification of the coating liquid and the conditions of the coating process.

The surface tension is preferably in the range of 15-36 [mN/m]. It is preferable to add a leveling agent to the coating liquid at the time of coating to lower the surface tension to prevent unevenness at the time of coating and is preferable. On the other hand, when the surface tension decreases too much, the possible coating speed in the above range decreases, so the surface tension is more preferably 17-32 [mN/m], even more preferably 19-26 [mN/m].

(filter)

The coating liquid used for coating is preferably filtered before coating. It is preferable that the filter for filtration has the smallest possible pore diameter within the range where components in the coating liquid are not removed. When filtering, use a filter with an absolute filtration accuracy of 0.1-10 μm, more preferably 0.1-5 μm. The thickness of the filter is preferably 0.1-10 mm, more preferably 0.2-2 mm. In this case, the filtration pressure is preferably 1.5 MPa or less, more preferably 1.0 MPa or less, even more preferably 0.2 MPa or less.

The member of the filter is not particularly limited as long as the filter has no adverse effect on the coating liquid. In particular, the same filter members as the above-mentioned wet-dispersed filter members of inorganic compounds are exemplified.

Furthermore, it is also preferable to ultrasonically disperse the filtered coating liquid immediately before coating in order to facilitate defoaming and maintain the dispersibility of the dispersion.

In the present invention, regarding the curing method of each layer of the antireflection film, it is preferably formed by a crosslinking reaction induced by light irradiation, electron beam irradiation and heating, or by a polymerization reaction while coating the coating composition or after coating. layers.

When each layer of the antireflection film is formed by a crosslinking reaction or polymerization of an ionizing radiation curable compound, it is preferable to perform the crosslinking reaction or polymerization in an atmosphere having an oxygen concentration of 10% by volume or less. By forming each layer in an atmosphere having an oxygen concentration of 10% by volume or less, an outermost layer excellent in physical strength and chemical resistance can be obtained.

The oxygen concentration is preferably 5% by volume or less, more preferably 1% by volume or less, especially preferably 0.5% by volume or less, most preferably 0.1% by volume or less.

As a means of obtaining an oxygen concentration of 10 vol% or less, air is preferably replaced with other gases (nitrogen concentration: about 79 vol% and oxygen concentration: about 21 vol%), and nitrogen replacement (nitrogen flushing) is particularly preferable.

The light source for light irradiation may be any of ultraviolet rays and near infrared rays. As the light source of ultraviolet rays, there are exemplified ultra-high pressure, high pressure, medium pressure and low pressure mercury lamps, chemical lamps, carbon arc lamps, metal halide lamps, xenon lamps and sunlight. Various laser light sources with a wavelength of 350-420nm that can be used can be made into multiple beams for irradiation. As a light source of near-infrared rays, a halogen lamp, a xenon lamp, and a high-pressure sodium lamp are exemplified, and various laser light sources with a wavelength of 750-1,400 nm that can be used can be made into multiple beams for irradiation.

When near-infrared light sources are used, they may be mixed with ultraviolet light sources, or light irradiation may be performed from the side of the substrate opposite to the side of the coating surface. Film curing is advanced in the depth direction of the coating without delay near the surface, so that a uniform and well-conditioned hardened film can be obtained.

The irradiation intensity of ultraviolet rays is preferably around 0.1-100 mW/cm ² , and the irradiation dose on the coating surface is preferably 10-1,000 mJ/cm ² . The temperature distribution of the coating during light irradiation is preferably controlled as uniform as possible, preferably within ±3°C, more preferably within ±1.5°C. Within this temperature range, the polymerization reaction proceeds uniformly in the in-plane direction and the depth direction of the layer and is preferable.

"The surface of the anti-reflection film opposite to the anti-reflection layer"

Where the antireflection film of the present invention is used as a polarizing plate, it is desirable to make the surface to be adhered to the polarizing plate hydrophilic, thereby improving the adhesive performance with the polarizing plate mainly made of polyvinyl alcohol.

The method of making the film hydrophilic is either (1) separately coating the above-mentioned layers (for example, light-diffusing layer, high-refractive-index layer, low-refractive-index layer, and hard coat layer) one by one onto a pre-hydrophilized support one or the other surface of the support, or (2) coating the above-mentioned layers (for example, a light-diffusing layer, a high refractive index layer, a low refractive index layer, and a hard coat layer) on one or the other surface of the support The surface that will be adhered to the polarizing sheet is then made hydrophilic. The method (2) is preferable to the method (1) because the surface on which the light-diffusing layer is coated is also made hydrophilic in the method (1), whereby it is difficult to ensure the adhesiveness between the support and the light-diffusing layer.

(hydrophilic treatment)

The surface of the support can be made hydrophilic by known methods. For example, treatment methods such as corona discharge treatment, glow discharge treatment, exposure to ultraviolet radiation, flame treatment, ozone treatment, acid treatment and alkali saponification are given to improve the surface of the film. These treatments are described in detail in Journal of Technical Disclosure No. 2001-1745 pp. 30-32.

(saponification)

Among these treatments, alkali saponification treatment is particularly preferred, and this treatment method is quite effective in surface-treated cellulose acylate films.

(1) Dipping method

It is a method of immersing the anti-reflective film in an alkali solution under appropriate conditions, and saponifying all the surfaces that react with the alkali on the entire film surface. This method is also preferred on a cost basis since no special equipment is required. Alkaline saponification solution includes potassium hydroxide solution and sodium hydroxide solution, preferably the normal concentration of hydroxide ion is 0.1-3.0N. Moreover, when the alkali saponification solution contains a solvent (for example, isopropanol, n-butanol, methanol, ethanol), a surfactant, or a wetting agent (for example, glycol, glycerin) having excellent wetting properties with a film, the alkali saponification solution The wetting properties with the support and the temporal stability are improved. The alkaline solution is preferably at a temperature of 20-70°C and more preferably 30-60°C.

After dipping in the alkaline solution, it is preferable that the film is thoroughly washed with water so that no alkaline compound remains on the film, or soaked in a dilute acid solution to neutralize the alkaline compound.

The other main plane of the support opposite the main plane with the light-diffusing layer is made hydrophilic by saponification. The protective film of the polarizing plate is often used in a state where the hydrophilic surface of the support is in contact with the polarizing plate.

The hydrophilic surface effectively improves the adhesive properties of the polarizing sheet mainly made of polyvinyl alcohol.

When water is formed between the surface of the support having the light-diffusing layer and the opposite surface thereof, it is more preferable to saponify with a lower contact in view of adhesiveness with the polarizing sheet. However, since the main plane with the light-diffusing layer is also damaged by the alkali treatment in this impregnation method, it is important to limit the reaction conditions to the minimum possible extent. When the damage of the alkali treatment anti-reflection layer is shown by the contact angle between the opposite principal planes of the support and water, for the support made of cellulose acylate film, the angle is preferably 20-50° and More preferably 30-45°. Within the above range, the antireflection film is hardly damaged and can maintain adhesiveness with the polarizing sheet, which is preferable.

(2) Method of coating alkaline solution

As a way of avoiding possible damage of the antireflection film in the above-mentioned dipping method, an alkali solution coating method is preferably used in which only the main plane and the opposite side of the main plane having the antireflection film are coated with an alkali solution under appropriate conditions and Go through steps such as heating, washing with water and drying. The alkaline solution and treatment have been described in JP-A-2002-82226 and International Publication No. 02/46809.

In a third embodiment, the following method can be used.

(1) The method of immersing the film in an alkaline solution

It is a method of immersing an antireflective film in an alkali solution under appropriate conditions to saponify all surfaces reacted with the alkali compound on the entire film surface, and is preferable in terms of reducing production costs because no special equipment is required. The alkaline solution is preferably an aqueous sodium hydroxide solution. The concentration is preferably 0.5-3 mol/L, especially preferably 1-2 mol/L. The alkaline solution is preferably at a temperature of 30-75°C and especially preferably 40-60°C.

Preferably, the saponification reaction should be carried out under relatively mild reaction conditions, which can be obtained by selecting the material or compound of the anti-reflection film or properly adjusting the target contact angle.

After dipping in the alkaline solution, it is preferable that the film is thoroughly washed with water so that no alkaline compound remains on the film, or soaked in a dilute acid solution to neutralize the alkaline compound.

The other surface of the transparent support opposite to the surface having the light-diffusing layer is made hydrophilic by saponification. The protective film of the polarizing plate is used in a state where the hydrophilic surface of the transparent support is in contact with the polarizing plate.

The hydrophilic surface effectively improves the adhesion of the adhesive layer mainly made of polyvinyl alcohol.

It is more preferable to form a lower contact angle and saponify between the surface of the transparent support on the side opposite to the surface having the low-refractive index layer and water in view of the adhesive performance with the polarizing sheet. However, since the surface with the low-refractive index layer and the inner light-scattering layer are also damaged by the alkali treatment in this impregnation method, it is important to limit the reaction conditions to the minimum possible extent. When the damage of the antireflection layer by alkali treatment is shown by the contact angle between the opposite surface of the transparent support and water, for a transparent support made of triacetyl cellulose, the angle is preferably 10-50° and more Preferably 30-50°, even more preferably 40-50°. In the above range, no damage occurs and adhesive properties are also improved. However, an angle of 50[deg.] or more causes a problem of adhesion to the polarizing sheet and is therefore not preferable. On the contrary, an angle smaller than 10° is large in damage to the anti-reflection film so that the physical strength is impaired, and thus is not preferable.

(2) Method of coating alkaline solution

As a way of avoiding possible damage to the antireflection film in the above-mentioned dipping method, an alkali solution coating method is preferably used in which an alkali solution is coated only on the opposite side of the surface having the antireflection film under appropriate conditions and passed through Steps such as heating, washing with water and drying. In this case, coating refers to bringing an alkaline solution or other substance into contact only with the surface to be saponified, and includes, in addition to spraying, a case of contacting with a tape containing a spraying liquid. However, these methods require additional equipment and processes for coating an alkaline solution, and are inferior to (1) the dipping method in terms of production cost. Since the alkaline solution only comes into contact with the saponified plane, it is possible to provide a layer on the opposite side using a material susceptible to damage by the alkaline solution. For example, evaporated thin films and sol-gel thin films are affected by alkaline solutions to cause corrosion, dissolution, peeling or other various problems. These films are not preferably used in the dipping method, but can be freely used in the coating method in which they do not come into contact with an alkaline solution.

Since saponification can be achieved by either of the above-mentioned methods (1) or (2) after forming a single layer, as a series of processes after the above-mentioned antireflection film preparation process, the The saponification of the film is carried out. The process of adhering the film to the polarizer can similarly be carried out continuously on the support of the unrolled film, whereby the polarizer is produced more efficiently by the sheet feeding process.

(3) A method of achieving saponification by laminating an antireflection film for protection

As in method (2), wherein at least one alkali-resistant solution is insufficient in the light-scattering layer or the low-refractive-index layer, forming the low-refractive-index layer and then adhering the laminated film on the surface on which the low-refractive-index layer is formed, and The resultant was dipped in an alkaline solution whereby only the plane of the triacetyl cellulose opposite to the plane on which the low-refractive index layer was formed became hydrophilic, after which the laminated film was peeled off. This method is also capable of imparting a hydrophilic treatment to the surface opposite to the surface of the antireflection layer on which the triacetyl cellulose film is formed, which is necessary for a polarizing plate, without damaging the light scattering layer or the low-refractive index layer. protective film. Compared with method (2), this method has the advantage of eliminating the need for special equipment for coating the alkali solution, although the laminated film must be discarded as waste.

(4) The method of immersing in an alkali solution after forming the light-scattering layer

The light-scattering layer and the layer below it are resistant to alkali solutions while the low-refractive-index layer is not so resistant to alkali solutions, and both sides of the light-scattering layer and the layer below it can be made hydrophilic by immersing them in an alkali solution after forming the light-scattering layer. treatment, thereby forming a low-refractive index layer on the light-scattering layer. The production process of this method is complicated, but its advantage is that it can improve the adhesion between the light-scattering layer and the low-refractive index layer, especially when the low-refractive index layer is a fluorine-containing sol-gel film or other materials containing hydrophilic groups. film.

(5) Method for forming an antireflection film on a saponified triacetyl cellulose film

In addition, the triacetyl cellulose film may be saponified in advance by dipping in an alkali solution or other substances, thereby forming a light-scattering layer or a low-refractive index layer on one or the other side of the film directly or through another layer . Where saponification is achieved by immersing the film in an alkaline solution, the saponification-treated triacetyl cellulose face loses adhesion to the light scattering layer or other layers and becomes hydrophilic. In this case, after such saponification, only the side on which the light-scattering layer or other layer is formed may be subjected to treatment such as corona discharge or glow discharge, thereby removing the hydrophilic side to successfully provide the light-scattering layer or other layers. Also, where the light scattering layer or other layers have hydrophilic groups, better interlayer adhesion can be provided.

(polarizer)

The polarizing plate of the present invention includes the above-mentioned antireflection film used in at least one or both protective films of the polarizing plate. In the present invention, the use of an antireflection film on the outermost surface can prevent reflection of external light, providing a polarizing plate excellent in scratch resistance, dust resistance, and other properties. Furthermore, in the polarizing plate of the present invention, an antireflection film can also be used as a protective film, thereby reducing production costs.

The following embodiments are also preferable as the antireflection film of the polarizing plate of the present invention.

(Structure of anti-reflection film)

The antireflection film of the present invention is made of a multilayer antireflection film consisting of at least two overlapping layers (light transmission layers) having light transmission properties and having different refractive indices from each other. The antireflection film composed of two overlapping layers is provided with a transparent protective film, a high refractive index layer and a low refractive index layer (outermost layer) and formed sequentially. The transparent protective film, the high-refractive-index layer, and the low-refractive-index layer have refractive indices satisfying the following relationship.

Refractive index of high refractive index layer > Refractive index of transparent protective film > Refractive index of low refractive index layer

A hard coat layer may also be provided between the transparent protective film and the high refractive index layer. Furthermore, the antireflection film can also be made of a high refractive index hard coat layer or an antiglare high refractive index layer and a low refractive index layer.

Provided to an antireflection film composed of at least three overlapping layers is a transparent protective film, a lower refractive index layer (medium refractive index layer) of two high refractive index layers, and a higher refractive index layer of two high refractive index layers (high refractive index layer) and low refractive index layer (outermost layer) and formed sequentially. The transparent protective film, the medium-refractive-index layer, the high-refractive-index layer, and the low-refractive-index layer have refractive indices satisfying the following relationship.

Refractive index of high refractive index layer > Refractive index of medium refractive index layer > Refractive index of transparent protective film > Refractive index of low refractive index layer

A hard coat layer may also be provided between the transparent protective film and the medium refractive index layer. Also, the antireflection film may be made of a medium refractive index layer, a hard coat layer, a high refractive index layer, and a low refractive index layer.

The above-mentioned multilayer product is made up of separate layers in such a way that the middle refractive index layer, the higher refractive index layer and the low refractive index layer can satisfy the following formula (IV- 2), (IV-3) and (IV-4), such multilayer products are preferred, because this layered structure can prepare antireflection film with better antireflection performance.

(IV-2): (m ₁ λ/4)×0.60<n ₁ d ₁ <(m ₁ λ/4)×0.80

(IV-3): (m ₂ λ/4)×1.00<n ₂ d ₂ <(m ₂ λ/4)×1.50

(IV-4): (m ₃ λ/4)×0.85<n ₃ d ₃ ＜(m ₃ λ/4)×1.05

where m ₁ is 1; n ₁ is the refractive index of the lower refractive index layer (medium refractive index layer) of the two high refractive index layers; d ₁ is the thickness (nm) of the middle refractive index layer; m ₂ is 2; n ₂ is the refractive index of the higher refractive index layer (high refractive index layer) among the two high refractive index layers; d ₂ is the thickness (nm) of the high refractive index layer; m ₃ is 1; n ₃ is the thickness of the low refractive index layer Refractive index; _d3 is the thickness (nm) of the low refractive index layer.

In the above-mentioned layered structure, the antireflection film can realize low reflection and color reduction of reflected light and reduction of color change due to incident angle. Therefore, a polarizing plate integrally formed with a transparent protective film superimposed on such an antireflection film, for example, for the first surface of a liquid crystal display device, can obtain a display device having hitherto unattainable high visibility. When the specular reflectance of incident light at an incident angle of 5° is 0.5% or less on average at a wavelength of 450nm to 650nm, it is possible to prevent a decrease in visibility due to reflection of external light on the surface of the display device; and the factor is 0.4% or less, reflection of external light can be substantially prevented.

If the incident light obtained from the CIE standard light source D65 within the wavelength of 380nm-780nm with an incident angle of 5° is the a ^* and b ^* of CIE1976L ^* a ^* b ^* in the color space of the regular reflected light (or specularly reflected light) The value is in the range of 0≤a ^* ≤7 and -10≤b ^* ≤0, and the incident angle is in the range of 5-45°. The other specular reflection light of the incident light at any angle can satisfy a ^* ≥ in the color space 0 and b ^* ≤ 0, then the color of the reflected light can be reduced at low incident angles and the color change with the incident angle of the reflected light can also be reduced.

Moreover, if the incident light is at any angle within the range of 5-45°, the specularly reflected light relative to the incident light is in the color space in C ^* = [(a ^* ) ² + (b ^* ) ² ] ^1/2 ≤ 12, it is possible to reduce the color of reflected light from magenta to blue-violet, which is a problem found in polarizers with conventional anti-reflective films, and also to reduce the color change depending on the incident angle of reflected light.

The color of the reflected light and the variation of this color with the angle of incidence can also be substantially reduced by keeping this value in the range of C ^* =[(a ^* ) ² +(b ^* ) ² ] ^1/2 ≦10. When the polarizing plate to which the antireflection film is fixed is used for a liquid crystal display device, the color presented by light reflection of external bright light such as light from indoor fluorescent lamps is neutralized in a wide incident angle and hardly feels uncomfortable .

More specifically, a value of a ^* > 0 will not exhibit a cyanogen-related color, while a value of b ^* < 0 will not exhibit a yellowish color, so this is preferred. Also, when the values a ^* ≥0 and b ^* ≤0 and C ^* =[(a ^* ) ² +(b ^* ) ² ] ^1/2 <12 are less likely to exhibit a magenta-like color, it is preferable.

A spectrophotometer V-550 [manufactured by JASCO Corporation] equipped with an adapter ARV-474 was used to measure specular reflectance and color. Specifically, measure the specular reflectance in the wavelength region of 380-780nm under the exit angle-θ and the angle of incidence θ (θ=5-45° and the interval is 5 degrees), and calculate the specular reflectance in the wavelength region of 450-650nm The average reflectance ratio to evaluate the anti-reflection performance. Also, by referring to the measured reflectance spectrum that can be used as a basis for evaluating the color of reflected light, L ^* of the CIE1976L ^* a ^* b ^* color space representing the color of specularly reflected light of incident light at a single incident angle with respect to the CIE standard illuminant D65 is calculated value, a ^* value and b ^* value.

Also, as explained above, the color of reflected light can be greatly reduced, which contributes to greatly reducing the color variation of reflected light caused by the irregular thickness of the antireflection film. That is, the allowable degree of irregular thickness is larger, thereby achieving efficient production and further reducing production cost.

The quantitative results can be determined by CIE standard light source D65 at a wavelength of 380nm-780nm at any two positions 10cm away from the TD direction (the direction perpendicular to the axial direction of the transparent protective film) and the MD direction (the axial direction of the transparent protective film). Indicated by the color change of the specularly reflected light against the incident light at an incident angle of 5°. In this case, the ΔEa ^* b ^* value of the CIE1976L ^* a ^* b ^* color space is preferably less than 2, more preferably less than 1.5, at which point roughness can no longer be detected with the naked eye.

In the present invention, the phrase "a ^* b ^* value or C ^* value at any incident angle of 5-45° is within the above-mentioned range" refers to specular reflection by incident light of 5-45° at an interval of 5° The a ^* value, b ^* value or C ^* value calculated by the spectrum is within the above range.

It is preferable that the high refractive index layer is a cured film having a refractive index of 1.55-2.50 using a cured compound containing inorganic compound fine particles having a high refractive index (hereinafter, they are also referred to as inorganic fine particles) and a matrix binder. . The refractive index is preferably 1.65-2.40, more preferably 1.70-2.20.

The high refractive index layer is preferably provided on a surface having a state of fine unevenness that does not cause any optical influence, and the arithmetic mean roughness (Ra) of the surface roughness of the high refractive index layer based on JIS B-0601-1994 is preferably 0.001 -0.03 μm, more preferably 0.001-0.015 μm, especially preferably in the range of 0.001-0.010 μm, and the ten-point average roughness (Rz) is preferably 0.001-0.06 μm, more preferably in the range of 0.002-0.05 μm, especially preferably in the range of 0.002-0.025 μm, the maximum height (Ry) is preferably 0.09 μm or less, more preferably 0.05 μm or less, and particularly preferably 0.04 μm or less. Also, in the above state of fine unevenness that does not cause any optical influence, it is preferable that the ratio (Ra/Rz) of the arithmetic mean roughness (Ra) to the ten-point mean roughness (Rz) is 0.15 or more, based on JIS The average distance (Sm) of the surface roughness of the high refractive index layer of B-0601-1994 is 0.01-1 μm. In this case, the relationship between Ra and Rz represents the uniformity of surface unevenness. More preferably the ratio (Ra/Rz) is greater than 0.17 and the average distance (Sm) is 0.01-0.8 μm. When the value is within the above range, the state of the layer coated on the high-refractive index layer is free from any unevenness or streaks, and is preferable, in which case the adhesiveness between these layers can be improved. The surface topography of the layers can be evaluated using atomic force microscopy (AFM).

When the high-refractive-index layer is made into a high-refractive-index cured film having a refractive index of 1.55 to 2.50 in which high-refractive-index inorganic fine particles are dispersed in a matrix binder, considering that the refractive index of the matrix binder is 1.4 The fact that -1.5, based on the refractive index of the fine particles, is used in a certain percentage. Specifically, the percentage is preferably 40-80% by weight, more preferably 45-75% by weight, based on the total weight of the cured film.

In order to increase the strength of the high-refractive index layer, by designing to contain a higher percentage of inorganic fine particles and to achieve greater adhesion with the upper layer to be formed, as described below, it is preferable to use inorganic fine particles with ultrafine particle size and uniform particle size. particles so that they are uniformly dispersed in the high-refractive index layer and provide the above-mentioned unevenness state on the surface of the layer. If the configuration and distribution of surface inhomogeneities on the entire surface of the high-refractive index layer are limited within a certain range, the upper layer can be provided with a sufficient anchoring effect on the entire surface, even if the upper layer is continuously fed as raw material to a long film, In this way, unevenness of the upper layer is preferably eliminated and good adhesion is maintained. In addition, even after long-term storage, the layer does not have any change in stickiness, and thus is also preferable.

In the present invention, the adhesiveness between the cured film of the high-refractive index layer and the upper layer (low-refractive-index layer) of the high-refractive index layer is preferably 50 mg using an abrasion meter measured by a Taber abrasion test based on JIS K-6902. or less, more preferably 40 mg or less. Specifically, the abrasion measured by the Taber abrasion test refers to the abrasion obtained after the test piece was rotated 500 times under a load of 1 kg. The antireflection film can maintain sufficient scratch resistance within the above range, and is preferable.

In the antireflection film including the high refractive index layer on which the surface pattern is formed, it is preferable that the number of highly visible luminance defects having a dust particle diameter of 50 μm or more is 20 pieces per square meter or less.

[Composition for forming high refractive index layer]

(inorganic fine particles with high refractive index)

In the present invention, the refractive index of the inorganic fine particles having a high refractive index contained in the high refractive index layer is preferably 1.80-2.80, more preferably 1.90-2.80. The average particle diameter of their primary particles is preferably 3-150 nm, more preferably 3-100 nm, especially preferably 5-80 nm. It is preferable that the refractive index of the inorganic fine particles is 1.80 or more to effectively increase the refractive index of the layer, and that problems such as coloring of particles do not occur where the refractive index is 2.80 or less. In addition, it is preferable that when the average particle diameter of the primary particles of the inorganic fine particles is 150 nm or less, problems such as a decrease in the transparency of the layer do not occur, and the haze value of the high refractive index layer thus formed increases, and it is also preferable that the inorganic fine particles The particles are 3nm or larger, so that the high refractive index can be maintained.

Preferable inorganic fine particles having a high refractive index include, for example, mainly composed of oxides, composite oxides or sulfides such as Ti, Zr, Ta, In, Nd, Sn, Sb, Zn, La, W, Ce, Nb, Particles composed of V, Sm and Y. In this case, the phrase "consisting essentially of" means that the compound constituting the particle is contained in the particle in the greatest percentage (weight %). More preferable inorganic fine particles usable in the present invention include particles mainly composed of oxides or composite oxides containing at least one metal element selected from Ti, Zr, Ta, In, and Sn.

Inorganic fine particles may contain various elements within the particles (hereinafter, these elements may be referred to as contained elements). The contained elements include, for example, Li, Si, Al, B, Ba, Co, Fe, Hg, Ag, Pt, Au, Cr, Bi, P, and S. In order to increase the conductivity of the particles, it is preferable to make tin oxide and indium oxide contain elements such as Sb, Nb, P, B, In, V and halogens, and it is especially preferable to make them contain about 5-20% by weight of antimony oxide.

Particularly preferable inorganic fine particles of the present invention are inorganic fine particles mainly composed of titanium dioxide containing at least one element selected from Co, Zr or Al as a contained element (hereinafter, they may be referred to as "specific oxide things"),. A particularly preferred contained element is Co. Based on Ti, the total amount of Co, Al or Zr is preferably 0.05-30% by weight, more preferably 0.1-10% by weight, even more preferably 0.2-7% by weight, especially preferably 0.3-5% by weight, most preferably 0.5-3% by weight weight%. The contained elements Co, Al and Zr exist in or on the inorganic fine particles mainly composed of titanium dioxide. They are more preferably present inside the inorganic fine particles mainly composed of titanium dioxide, and most preferably both in and on the inorganic fine particles. Among these contained elements, metal elements may exist in the form of oxides.

Also, other preferable inorganic fine particles include composite oxides and particles having at least one metal element selected from titanium and metal elements having a refractive index of 1.95 or more (hereinafter, they may be abbreviated as "Met") , wherein the composite oxide is an inorganic fine particle composed of at least one doped metal ion selected from Co ions, Zr ions, and Al ions (they may be referred to as "specific composite oxides"). In this case, preferable metal elements in which the refractive index of the oxide is 1.95 or more include Ta, Zr, In, Nd, Sb, Sn, and Bi. Ta, Zr, Sn and Bi are particularly preferred. In consideration of maintaining the refractive index, the metal ions doped with the composite oxide should preferably occupy an amount of not more than 25% by weight based on the total metal amount [Ti+Met] constituting the composite oxide. The content of metal ions is more preferably 0.05-10% by weight, still more preferably 0.1-5% by weight, most preferably 0.3-3% by weight.

The dopant metal ion may exist as a metal ion or any form of the metal ion and may exist substantially on the surface or inside the composite oxide, preferably both on and inside the composite oxide.

It is preferable that the inorganic fine particles have a crystal structure. It is also preferred that the crystal structure consists essentially of rutile, rutile/anatase mixed crystals and anatase, more preferably it consists essentially of rutile. Such a structure is preferable because the inorganic fine particles of the specific oxide or the specific composite oxide have a refractive index of 1.90 to 2.80. The refractive index is preferably 2.10-2.80, more preferably 2.20-2.80. This structure is also preferable because it can suppress the photocatalytic activity of titanium dioxide, thus remarkably improving the weather resistance of the high refractive index layer of the present invention and the weather resistance of the upper and lower layers contacting the high refractive index layer.

The above specific metal elements and metal ions can be doped by well-known conventional methods. For example, they can be obtained by the methods described in JP-A-5-330825, JP-A-11-263620, International Application Japanese Translation (Kohyo) No.H11-512336, EP-A.No.0335773 or by ion implantation Into the law [eg, "Ion beam application technology", edited by Gonda S., Ishikawa J. and Kamijo E., CMC Ltd., 1989 publication; Aoki Y., "Hyomenkagaku," Vol. 18(5), No. 262 pp., 1998; and Yasuho S. et al. "Hyomenkagaku," Vol. 20(2), p. 60, 1999] doping.

Inorganic fine particles may be surface-treated. The purpose of surface treatment is to use inorganic compounds and/or organic compounds to improve the surface quality of the particles, as a result, the wetting properties of the surface of the inorganic fine particles can be adjusted, the abrasiveness in organic solvents can be improved, and in the compound forming the high refractive index layer Dispersion Stable dispersion. Inorganic compounds that physically adsorb onto particle surfaces include, for example, silicon-containing inorganic compounds (such as SiO ₂ ), aluminum-containing inorganic compounds [such as Al ₂ O ₃ and Al(OH) ₃ ], cobalt-containing inorganic compounds (such as CoO ₂ , Co ₂ O ₃ and Co ₃ O ₄ ), zirconium-containing inorganic compounds [such as ZrO ₂ and Zr(OH) ₄ ], and iron-containing inorganic compounds (such as Fe ₂ O ₃ ).

Organic compounds that can be used for surface treatment include surface modifiers such as inorganic fillers composed of known metal oxides, inorganic pigments, and others. They are described, for example, in Chapter 1 of "Stable Dispersion and Surface Treatment Process/Evaluation of Pigments" (published by the Technical Information Institute Co., Ltd., 2001) and others.

Specifically, the organic compound includes an organic compound and a coupling compound having a polar group compatible with the surface of the inorganic fine particles. Polar groups that can be compatible with the surface of inorganic fine particles include carboxyl groups, phosphono groups, hydroxyl groups, mercapto groups, cyclic acid anhydride groups, and amino groups. Preferred compounds are those containing at least one of these groups in the molecule, for example, long-chain aliphatic carboxylic acids (e.g. stearic acid, lauric acid, oleic acid, linoleic acid, linolenic acid), polyols (e.g. Pentaerythritol triacrylate, dipentaerythritol pentaacrylate, ECH (epichloropyridone), modified glyceryl triacrylate), compounds containing phosphono groups (such as EO (ethylene oxide), modified phosphate triacrylate ) and alkanolamines (eg ethylenediamine EO adduct (5 mol)).

Coupling compounds include well-known conventional organometallic compounds, such as silane coupling agents, titanate coupling agents, and aluminate coupling agents. Most preferred are silane coupling agents. Specifically, they are compounds described in paragraphs 0011-0015 of JP-A-2002-9908 and JP-A-2001-310423.

These compounds for surface treatment may be used in combination of two or more.

It is also preferable to form inorganic fine particles having a core/shell structure with other inorganic compounds on the basis of the inorganic fine particles as the core. A preferable shell is an oxide composed of at least one element selected from Al, Si and Zr, as described in JP-A-2001-166104, for example.

The shape of the inorganic fine particles is not particularly limited, and is preferably a granule, a sphere, a cube, a spindle, or an amorphous shape. Inorganic fine particles may be used alone or in admixture of two or more.

(Dispersant)

In order to use inorganic fine particles as the aforementioned stable ultrafine particles, it is preferable to add a dispersant. Preferable dispersants include low-molecular compounds or high-molecular compounds containing polar groups that can be compatible with the surface of inorganic fine particles.

Polar groups include hydroxyl, mercapto, carboxyl, sulfo, phosphono, hydroxyphosphoryl, -P(=O)(R ₁ )(OH) groups, -OP(=O)(R ₁ )(OH) groups groups, amide groups (-CONHR ₂ , -SO ₂ NHR ₂ ), cyclic anhydride-containing groups, amino groups and quaternary ammonium groups.

In this case, R represents a hydrocarbon radical having ₁ to 18 carbon atoms (for example, methyl, ethyl, propyl, butyl, hexyl, octyl, decyl, dodecyl, octadecyl chloroethyl, methoxyethyl, cyanoethyl, benzyl, methylbenzyl, phenethyl and cyclohexyl). R ₂ represents a hydrogen atom or the same meaning as R ₁ .

Among the above-mentioned polar groups, a group having a dissociated proton may be a salt thereof. Also, the aforementioned amino groups and quaternary ammonium groups may be any primary, secondary or tertiary amino groups. Tertiary amino groups and quaternary ammonium groups are more preferred. Groups which are preferably combined with nitrogen atoms in secondary amino groups, tertiary amino groups or quaternary ammonium groups are aliphatic groups with 1 to 12 carbon atoms (identical in meaning to the _R1 or _R2 groups described above). Also, the tertiary amino group may be a cyclic amino group containing a nitrogen atom (eg, piperidine ring, morpholine ring, piperazine ring, and pyridine ring), and the quaternary ammonium group may be a quaternary ammonium of these cyclic amino groups. An alkyl group having 1 to 6 carbon atoms is particularly preferred.

Counterions of quaternary ammonium groups are preferably halides, PF ₆ ions, SbF ₆ ions, BF ₄ ions, B(R ₃ ) ₄ ions (R ₃ represents a hydrocarbyl group, and for example, butyl, phenyl, tolyl, naphthyl and butylphenyl) and sulfonate ions.

The polar groups of the dispersant are preferably salts of anionic groups with a pKa of 7 or less and their dissociative groups. Particular preference is given to salts of carboxyl, sulfo, phosphono; hydroxyphosphoryl or their dissociating groups.

Preferably the dispersant also contains crosslinking or polymerizing functional groups. Cross-linking or polymerizing functional groups include groups capable of undergoing free radicals [e.g., (meth)acryl, allyl, styryl, vinyloxy, and carbonyl], cationic polymerizing groups (e.g., epoxy, thiocyclic Oxygen, oxetanyl, ethyleneoxy, spiroorthoester group) and polycondensation reaction groups (hydrolyzed silyl, N-methylol) for addition reaction and polymerization of unsaturated ethylene . Preference is given to unsaturated ethylene, epoxy and hydrolyzed silyl groups.

Specifically, they are compounds described in paragraphs [0013] to [0015] in the specification of JP-A-2001-310423.

The dispersants that can be used in the present invention are preferably polymeric dispersants, especially polymeric dispersants containing anionic groups and cross-linking or polymerizing functional groups. The polymer dispersant has no particular limitation on the weight average molecular weight (Mw). Based on the polystyrene conversion of GPC (gel permeation chromatography), the preferred Mw is greater than 1×10 ³ , the more preferred Mw is 2×10 ³ to 1×10 ⁶ , and the even more preferred Mw is 5×10 ³ to 1×10 ⁵ , and a particularly preferred Mw is 8×10 ³ to 8×10 ⁴ . Dispersants with Mw within these ranges are preferred because inorganic fine particles can be easily dispersed to provide a stable dispersion without aggregation or precipitation. Examples are those described in paragraphs [0024] to [0041] in the specification of JP-A-11-153703.

(dispersion medium)

The dispersion medium used for treating inorganic fine particles by wet dispersion can be roughly selected from water or organic solvents. Liquids with a boiling point of 50°C or higher are preferred, and organic solvents with a boiling point of 60 to 180°C are more preferred.

The dispersion medium is preferably used in an amount of 5 to 50% by weight, more preferably 10 to 30% by weight, based on the total amount for forming the high refractive index layer containing the inorganic fine particles and the dispersant. Within these ranges, the dispersion proceeds smoothly to provide the resulting dispersed material with a viscosity allowing better processability.

Dispersion media include alcohols, ketones, esters, amides, ethers, ethers/esters, hydrocarbons and halogenated hydrocarbons. Specifically, they include alcohols (e.g., methanol, ethanol, propanol, butanol, benzyl alcohol, ethylene glycol, propylene glycol, and ethylene glycol monoacetate), ketones (e.g., methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and methylcyclohexanone), esters (for example, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl formate, propyl formate, butyl formate and ethyl lactate), aliphatic hydrocarbons (e.g., hexane and cyclohexane), halogenated hydrocarbons (e.g., methyl chloroform), aromatic hydrocarbons (e.g., benzene, toluene, and xylene), amides (e.g. , dimethylformamide, dimethylacetamide, and N-methylpyrrolidone), ethers (e.g., dioxane, tetrahydrofuran, ethylene glycol dimethyl ether, and propylene glycol dimethyl ether), ether alcohols (e.g. , 1-methoxy-2-propanol, ethyl cellosolve and methylmethanol). They may be used alone or in combination of two or more. Preferred dispersion media include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and butanol. It is also preferable to use a coating solvent mainly composed of a ketone solvent (for example, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone). The content of the ketone solvent is preferably 10% by weight or more, more preferably 30% by weight or more, and still more preferably 60% by weight or more, based on all solvents contained in the high-refractive index layer-forming compound.

(Ultragrinding of Inorganic Fine Particles)

When the cured high-refractive index layer-forming compounds usable in the present invention are prepared as ultrafine particle dispersions of inorganic compounds having an average particle diameter of 100 nm or less, these compounds are more stable in liquids, and the compounds formed from these cured compounds The high refractive index layer of the cured film can be utilized in such a manner that inorganic fine particles are uniformly dispersed in the matrix of the cured film in an ultrafine particle state to provide a transparent high refractive index layer with uniform optical properties. The ultrafine particles present in the matrix of the cured film preferably have an average particle size of 3-100 nm, more preferably 5-100 nm, most preferably 10-80 nm. It is also preferably free of larger particles with an average particle diameter of 500 nm or more, particularly preferably free of larger particles with a particle diameter of 300 nm or more. Under these conditions, it is preferable to impart the above-mentioned specific unevenness to the surface of the cured film.

The dispersion of the above-mentioned high-refractive-index inorganic fine particles existing in the state of ultrafine particles and having no large particles of the above-mentioned range of particle diameters can be obtained by a wet dispersion method and adding a dispersant and a medium with an average particle diameter of less than 0.8 mm.

Wet dispersing machines include well-known conventional devices such as sand mills (for example, bead mills with pins), bead mills, high-speed impeller mills, pebble ball mills, rolling mills, attritors, and colloid mills. A sand mill, a bead mill, and a high-speed impeller mill are particularly preferable to disperse the inorganic fine particles of the present invention into ultrafine particles.

The medium used with the above-mentioned disperser preferably has an average particle diameter of 0.8 mm or less. Using a medium having the above-mentioned average particle diameter can obtain inorganic fine particles having a diameter of less than 100 nm and also provide ultrafine particles having a uniform particle diameter. The average particle size of the media is more preferably 0.5mm or less, even more preferably 0.05-0.3mm. Preferred media for wet dispersion are beads, more specifically zirconia beads, glass beads, ceramic beads and steel beads. In view of corrosion resistance, zirconia beads with a diameter of 0.05-0.2 mm are particularly preferred so that they are less often broken (more durable) during dispersion and supergrinding.

The dispersion temperature in the dispersion process is preferably 20-60°C, more preferably 25-45°C. Within these temperature ranges, the dispersed particles no longer aggregate or precipitate in the state of ultrafine particles on the dispersion, which is preferred in the present invention. This result is considered to be due to the fact that the dispersant is roughly adsorbed on the inorganic compound, and the dispersion is not destabilized due to desorption of particles of the dispersant at normal temperature. When the dispersion process is performed within these temperature ranges, a high-refractive-index film that is not affected by transparency, has a uniform refractive index, has greater strength, and is excellent in adhesion to adjacent layers can be provided.

A pre-dispersion treatment may be performed prior to the above wet dispersion process. Dispersers that can be used for the pre-dispersion treatment may include ball mills, three-roll mills, kneaders, and extruders.

During the separation of the beads it is preferred to provide a filter medium for microfiltration to remove large agglomerates in the dispersion so that the dispersed particles in the dispersion can be monodisperse in terms of average particle size and particle size within the above range satisfactory. The filter medium for microfiltration preferably has a filter particle size of 25 μm or less. The filter medium for microfiltration is not particularly limited in type as long as it satisfies the above properties, which include, for example, filament type, felt type, and mesh type. The filter medium for microfiltration of dispersion is not particularly limited in material as long as it satisfies the above properties and does not affect the compound forming the high refractive index layer, and includes, for example, stainless steel, polyethylene, polypropylene, and nylon.

(Matrix of high refractive index layer)

It is preferable that the high-refractive index layer contains high-refractive-index inorganic fine particles and a matrix.

According to a preferred embodiment of the present invention, the matrix of the high refractive index layer is formed by coating and curing a high refractive index layer-forming compound containing (A) an organic binder or (B) a hydrolyzable functional group At least one of an organometallic compound and a partial condensate of the organometallic compound.

(A) Organic binder

Organic binders include (a) known conventional thermoplastic resins, (b) combinations of known conventional reactive curing resins and curing agents, or (c) binder precursors (multifunctional curing monomers and The adhesive formed by the combination of polyfunctional oligomer) and polymerization initiator.

It is preferable that the high-refractive-index layer-forming compound is prepared by dispersing a solution containing the above (a), (b) or (c) organic binder, high-refractive-index inorganic fine particles and a dispersant. The compound is coated on a transparent protective film to form a film, and the formed film is cured according to the binder-forming compound, thereby providing a high refractive index layer. The curing method can be appropriately selected according to the type of adhesive compound. For example, applying at least one of heat or exposure to light to the curable compounds (eg, polyfunctional monomers and polyfunctional oligomers) to crosslink or polymerize. In addition, preferred is a method of using the above (c) composition and exposing it to light, thereby crosslinking or polymerizing the curing compound to provide a cured adhesive.

It is also preferable to subject the dispersant contained in the dispersion liquid of the high-refractive-index inorganic fine particles to crosslinking or polymerization simultaneously with or after coating the high-refractive-index layer-forming compound.

Therefore, the adhesive produced in the cured film can be used by, for example, cross-linking or polymerizing a multifunctional curing monomer (precursor of a dispersant and an adhesive) and a multifunctional oligomer and the dispersant Anionic groups are added to the binder. Moreover, since the anionic group has the function of keeping the fine inorganic particles dispersed in the binder of the cured film, the crosslinked or polymerized structure imparts film-forming ability to the binder, thereby improving the Physical strength, chemical resistance and weatherability of the cured film.

The above (a) thermoplastic resins include polystyrene resins, polyester resins, cellulose resins, polyether resins, vinyl chloride resins, vinyl acetate resins, vinyl chloride/ethylene oxide copolymer resins, polyacrylate resins, polymethyl Acrylate resins, polyolefin resins, urethane resins, polysiloxane resins, and imide resins.

It is also preferable to use a thermosetting resin and/or an ionizing radiation curable resin as the above (b) reactive curable resin. Thermosetting resins include phenolic resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, amino alkyd resin, melamine urea co-condensation Resin, silicone and polysiloxane resins. Ionizing radiation curable resins contain functional groups such as radically polymerizable unsaturated groups [(meth)acryloxy, vinyloxy, styryl and vinyl] and/or cationically polymerizable groups (epoxy, Thioepoxy, vinyloxy, oxetanyl resins, e.g. relatively low molecular weight polyester resins, polyether resins, (meth)acrylate resins, epoxy resins, urethane resins, alcohol Acid resins, spiroacetal resins, polybutadiene resins and polythiol-polyene resins.

If necessary, to these reactive curing resins, well-known conventional compounds such as crosslinking agents (such as epoxy compounds, polyisocyanate compounds, polyol compounds, polyamine compounds, melamine compounds), polymerization initiators (ultraviolet light Initiators such as azobis compounds, organic peroxide compounds, organic halogen compounds, monosalt compounds, ketone compounds), curing agents, polymerization accelerators (such as organic metal compounds, acid compounds, alkali compounds). Specifically, conventional compounds are compounds described in "Handbook of Crosslinking Agents" edited by Yamashita S. and Kaneko T (Taiseisha Co., Ltd., 1981).

Hereinafter in this specification, a preferred method of forming a cured adhesive is mainly explained, ie, using the above (c) composition to crosslink and polymerize the curing compound by exposure to light, thereby providing a method of curing the adhesive.

The functional groups of the photocurable polyfunctional monomers and polyfunctional oligomers may be radical polymerization groups or cationic polymerization groups.

Radical polymerizable functional groups include unsaturated ethylene groups such as (meth)acryloyl, vinyloxy, styryl and allyl groups. (Meth)acryloyl is preferred. Polyfunctional monomers containing two or more radically polymerizable groups in the molecule are preferred.

The radically polymerizable polyfunctional monomer is preferably selected from compounds having at least 2 terminal ethylene unsaturated bonds. Preferred compounds are those having 2 to 6 terminal ethylene unsaturated bonds in the molecule. Such compounds are well known in the field of polymer materials, and can be used in the present invention without any limitation. These compounds may be used in chemical forms such as monomers, prepolymers (dimers, trimers and oligomers), mixtures and copolymers thereof.

Radical polymerizable monomers include unsaturated carboxylic acids (for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid) and their esters and amides, preferably unsaturated carboxylic acids and Esters of aliphatic polyol compounds, unsaturated carboxylic acids and amides such as aliphatic polyamine compounds.

It is also preferred to use the addition reaction products of monofunctional or polyfunctional isocyanates and epoxides with unsaturated carboxylic acid esters and amides having nucleophilic substituents such as hydroxyl, amino and mercapto groups, or their addition with polyfunctional carboxylic acids dehydration condensation reaction product. Furthermore, reaction products of unsaturated carboxylic acid esters or amides having electrophilic substituents such as isocyanate groups and epoxy groups with monofunctional or polyfunctional alcohols, amines and thiols can preferably also be used. As other examples, unsaturated phosphoric acid, styrene, or other substances may also be used instead of the aforementioned unsaturated carboxylic acid compounds.

Aliphatic polyvalent alcohol compounds include alkanediol, alkanetriol, cyclohexanediol, cyclohexanetriol, inositol, cyclohexanedimethanol, pentaerythritol, sorbitol, dipentaerythritol, tripentaerythritol, glycerol and diglycerin. Also included are polymeric ester compounds (monoesters or polyesters) of their aliphatic polyol compounds and unsaturated carboxylic acids, for example, compounds described in paragraphs [0026] to [0027] of JP-A-2001-139663.

Other polymeric esters preferred for use in the present invention are, for example, vinyl methacrylate, allyl methacrylate, allyl acrylate, Japanese Published Examined Patent Application S46-27926 and Japanese Published Examined Patent Application S51-47334 and aliphatic alcohol esters described in JP-A-57-196231, those polymeric esters having an aromatic skeleton described in JP-A-2-226149, and those having an amino group described in JP-A-1-165613 Polyester.

In addition, polymeric amides composed of aliphatic polyamine compounds and unsaturated carboxylic acids include, for example, methylene bis(meth)acrylamide, 1,6-hexamethylene bis(meth)acrylamide, diethylene bis(meth)acrylamide, triamine tri(meth)acrylamide, xylene di(meth)acrylamide, and those polymeric amides having a cyclohexene structure described in Japanese Published Examined Patent Application S54-21726.

Others that can be used are vinyl urethane compounds containing two or more polymerized vinyl groups in one molecule (Japanese Published Examined Patent Application S48-41708, etc.), urethane acrylates (Japanese Published Examined Patent Application H2 -16765, etc.), urethane compounds having an oxirane skeleton (Japanese published and examined patent application S62-39418, etc.), polyester acrylates (Japanese published and examined patent application S52-30490, etc.) and The Journal of the Those photocurable monomers and oligomers described in Adhesion Society of Japan, Vol. 20: No. 7, 300-308 (1984).

These radically polymerizable polyfunctional monomers may be used in combination of two or more.

Next, a cationically polymerizable group-containing compound (hereinafter referred to as "cationically polymerizable compound" or "cationically polymerizable organic compound") usable as a binder for forming a high-refractive index layer is explained.

Any compound capable of causing polymerization and/or crosslinking when exposed to active energy rays in the presence of an active energy ray-sensitive cationic polymerization initiator can be used as the cationically polymerizable compound in the present invention. Examples include epoxy compounds, cyclic sulfide compounds, cyclic ether compounds, spiroorthoester compounds, vinyl hydrocarbon compounds, and vinyl ether compounds. One or two or more of the above cationic polymer compounds may be used in the present invention.

The compound containing cationically polymerizable groups preferably contains 2-10 cationically polymerizable groups in one molecule, particularly preferably 2-5. The molecular weight of the compound is 3,000 or less, preferably in the range of 200-2,000, particularly preferably in the range of 400-1,500. Keeping the molecular weight at the lower limit or more does not cause any troubles such as problematic volatilization during film formation, while keeping the molecular weight at the upper limit or less does not cause troubles such as compatibility with the compound of the high refractive index layer. Poor capacity. Therefore, this molecular weight range is preferred.

Epoxy compounds include aliphatic epoxy compounds and aromatic epoxy compounds.

Aliphatic epoxy compounds include, for example, polyglyceryl ethers of aliphatic polyhydric alcohols or alkylene oxide addition products, aliphatic long-chain polyacids of polyglycidyl esters, polyglycidyl acrylates and polyglycidyl methacrylates Homopolymer or Copolymer. In addition to epoxy compounds, the present invention can also use aliphatic higher alcohols of monoglycidyl ethers, higher fatty acids of glycidyl esters, epoxidized soybean oil, epoxy stearic acid, butyl epoxy octyl stearate , epoxidized linseed oil and epoxidized polybutadiene. In addition, cycloaliphatic epoxy compounds include polyols of polyglycidyl ethers having at least one alicyclic ring and compounds containing cyclohexane oxide or cyclopentene oxide, which are obtained by using a suitable oxidizing agent such as hydrogen peroxide or Superacid products, obtained by oxidation of compounds containing unsaturated alicyclic rings (for example, cyclohexane, cyclopentene, dicyclooctane or tricyclodecene).

In addition, aromatic epoxy compounds include monovalent or polyvalent phenols, monomers of alkylene oxide addition products, and polyglycidyl ethers containing at least one aromatic nucleus. These epoxy compounds include, for example, compounds described in paragraphs [0084] to [0086] of JP-A-11-242101 and compounds described in paragraphs [0044] to [0046] of JP-A-10-158385 the compounds mentioned.

Among these epoxy-based compounds, aromatic epoxides and alicyclic epoxides are preferred, and alicyclic epoxides are particularly preferred when rapid curing properties are considered. In the present invention, the above-mentioned epoxy-based compounds may be used alone or in admixture of two or more kinds.

Cyclic thioether compounds include compounds in which the above epoxy ring is changed to a thioepoxy ring.

Compounds containing an oxetanyl group as a cyclic ether include, for example, those described in paragraphs [0024] to [0025] of JP-A-2000-239309. These compounds are preferably used in admixture with epoxy group-containing compounds.

Spiroorthoester compounds include, for example, those described in JP-T-2000-506908.

Vinyl hydrocarbon compounds include styrene compounds, vinyl-substituted alicyclic hydrocarbon compounds (vinylcyclohexane, vinylbicycloheptene), compounds described as radically polymerizable monomers, (Journal of Polymer Science: Part A: Acryl compounds described in Polymer Chemistry, Vol. 32, 2895 (1994)), alkoxypropylene compounds described in (Journal of Polymer Science: Part A: Polymer Chemistry, Vol. 33, 2493 (1995)) vinyl compounds described in (Journal of Polymer Science: Part A: Polymer Chemistry, Vol. 34, 1015 (1996) and JP-A-2002-29162 ) and (Journal of Polymer Science: Part A: Polymer Chemistry Isopropenyl compounds described in Chemistry, Vol. 34, 2051 (1996)). They can be used in combination of two or more.

Furthermore, the molecule of the polyfunctional compound preferably contains at least one of a radically polymerizable group and a cationically polymerizable group. Examples include compounds described in paragraphs [0031] to [0052] of JP-A-8-277320 and paragraph [0015] of JP-A-2000-191737. Compounds usable in the present invention are not limited to these.

Based on the weight ratio of the radical polymerizable compound to the cationic polymerizable compound, the preferred content ratio of the radical polymerizable compound and the cationic polymerizable compound is 90:10-20:80, more preferably 80:20-30:70.

Next, the polymerization initiator used in combination with the binder precursor for the composition described in (C) above will be described in detail.

Polymerization initiators include thermal polymerization initiators and photopolymerization initiators.

Preferred polymerization initiators are compounds that generate free radicals or acids on exposure to light and/or heat. The maximum absorption wavelength of the photopolymerization initiator is preferably less than 400 nm. The initiator can operate under incandescent light by converting this wavelength into the ultraviolet region. Compounds having a maximum absorption wavelength in the near-infrared region can also be used.

First, the compounds that generate free radicals are specified.

The free radical generating compound preferably used in the present invention is a compound that generates free radicals upon exposure to light and/or heat and initiates and promotes polymerization of compounds having polymerizable unsaturated groups. Known polymerization initiators and compounds having low bond cleavage energy can be appropriately selected and used in the present invention. Also, the radical-generating compounds may be used alone or in admixture of two or more.

The radical-generating compound includes, for example, thermal radical polymerization initiators such as well-known conventional organic peroxide compounds and azo polymerization initiators, and photoradical polymerization initiators such as organic peroxide compounds (JP-A- 2001-139663, etc.), amine compounds (JP-A-44-20189), metallocene compounds (JP-A-5-83588, JP-A-1-304453, etc.), hexaaryldiimidazole compounds (USP No. 3,479,185, etc.), disulfone compounds (JP-A-5-239015, JP-A-61-166544, etc.), organic halogenated compounds, carbonyl compounds and organic boronic acid compounds.

The above-mentioned organic halogenated compounds include, for example, "Bull Chem. Soc. Japan", Wakabayashi et al., 42, 2924 (1969), USP No. 3,905,815, JP-A-5-27830, M.P. Hutt, "Journal of Heterocyclic Chemistry" 1 (No 3), the compound described in (1970). Particular preference is given to trihalomethyl-substituted oxazole compounds: s-triazine compounds. More preferred are s-triazine derivatives in which at least one of the monohalogenated, dihalogenated or trihalogenated methyl groups is bonded to the s-triazine ring.

The above-mentioned carbonyl compounds include "Latest UV curing technology" published by Technical Information Institute Co., Ltd., 1991, pp. 60-62, paragraphs [0015]-[0016] of JP-A-8-134404 and JP-A - Compounds described in paragraphs [0029] to [0031] of 11-217518, for example, benzoin compounds such as acetophenones, hydroxyacetophenones, benzophenones, thialkanes, benzene Azoin ethers and benzoin isobutyl ethers, ethyl benzoate derivatives such as p-dimethylaminoethyl benzoate, p-diethylaminoethyl benzoate, benzyl dimethylaminoethyl benzoate Ketones and acylphosphine oxides.

The above organic borate compounds include those described in Japanese Patent No. 2764769, JP-A-2002-116539 and Kunz, Martin, "Rad Tech'98. Proceeding April 19-22, 1998, Chicago". They are, for example, compounds described in paragraphs [0022]-10027] of JP-A-2002-116539. Also, other organoborate compounds include those described in JP-A-6-348011, JP-A-7-128785, JP-A-7-140589, JP-A-7-306527 and JP-A-7-292014 The boron transition metal coordination complex described above.

These radical-generating compounds may be added alone or in admixture of two or more. Based on the total amount of free-radical polymerizable monomers, the radical-generating compound can be added in an amount of 0.1-30% by weight, preferably 0.5-25% by weight, especially preferably 1-20% by weight. Within the above range, the compound of the high refractive index layer is stable over a period of time and can provide higher polymerization.

Next, a photoacid generator usable as a photopolymerization initiator will be described in detail.

The acid generator includes well-known compounds and their mixtures such as photoinitiators for photocationic polymerization, light color removers and light-altering agents for coloring substances or well-known acid generators used in microetching techniques, and the like. In addition, acid generators include organic halogenated compounds, disulfone compounds, and -compounds, wherein organic halogenated compounds and disulfone compounds are particularly similar to compounds that generate free radicals.

_ compounds include diazonium salts, ammonium salts, imine _ salts, phosphonium salts, iodonium _ salts, sulfonium salts, potassium salts and selenium _ salts. Specifically, they are compounds described in paragraphs [0058] to [0059] of JP-A-2002-29162.

As for acid generators, acetylene salts are preferably used in the present invention. Among them, diazonium-salts, iodine-salts, sulfonium-salts, and iminium-salts are preferably used in consideration of photosensitivity to initiate photopolymerization and stability of raw materials of the compound.

The salts preferably used in the present invention are, for example, pentylsulfonium salts described in paragraph [0035] of JP-A-9-268205, paragraphs [0010] to [0011] of JP-A-2000-71366 Diaryl iodonium salts and triaryl sulfonium salts described in paragraphs, sulfonium salts of thiobenzoic acid-S-phenyl esters described in paragraph [0017] of JP-A-2001-288205, and JP-A - the salts described in paragraphs [0030]-[0033] of 2001-133696.

Other examples of acid generators include compounds such as organometallic/organohalogenated products, photoacid generators having o-nitrobenzyl-type protecting groups, and articles [0059]-[0062 of JP-A-2002-29162 A compound (iminosulfonate, etc.) that produces sulfonic acid by photolysis described in the paragraph ].

These acid generators may be used alone or in combination of two or more. Based on the total weight of all cationic polymerizable monomers (100 parts by weight), these acid generators may be added in an amount of 0.1-20 wt%, preferably 0.5-15 wt%, especially preferably 1-10 wt%. In consideration of the stability of the compound with a high refractive index and the better performance of the polymerization reaction, the above-mentioned addition range is preferable.

The compound used in the high refractive index layer of the present invention preferably contains 0.5 to 10% by weight of a radical polymerization initiator or 1 to 10% by weight of a cationic polymerization initiator, based on the total weight of the radical polymerization compound and the cation polymerization compound. It is more preferable to contain 1 to 5% by weight of a radical polymerization initiator or 2 to 6% by weight of a cationic polymerization initiator.

When polymerized by ultraviolet radiation, the compound forming the high refractive index layer of the present invention may be used in admixture with known conventional ultraviolet spectrum sensitizers and chemical sensitizers. These sensitizers include Michler's ketone (Michler), amino acids (glycine, etc.) and organic amines (butylamine, dibutylamine, etc.).

When the polymerization reaction is carried out by exposure to near-infrared rays, it is preferable to mix and use a near-infrared spectrum sensitizer. The near-infrared spectrum sensitizer used in combination may include a light-absorbing substance having an absorption band in at least a part of the wavelength range of 700 nm or more. Compounds having a molecular absorption constant of 10,000 or more are preferred, and those having absorption in the region of 750 to 1400 nm and having a molecular absorption constant of 20,000 or more are more preferred. Most preferred are optically transparent compounds having an absorption end in the visible wavelength range from 420nm to 700nm.

The near infrared spectrum sensitizer may include various pigments and dyes known as near infrared absorbing pigments and near infrared absorbing dyes. Among these products, it is preferable to use a well-known conventional near-infrared ray absorbing agent. Commercially available dyes and literature [eg, "Near-infrared rayabsorbing coloring matters", "Chemical Industry, May 1986, 45-51; "Development of functional coloring matters and market trend in the 1990s," Chapter 2, Chapter 2 Section and Section 3 (1990), CMC; "Special functional coloring matters" edited by Ikemori and Hashiratani, 1986, published by CMC] J.FABIAN, Chem.Rev., Vol. 92, 1197-1226, 1992], the Nihon KankoShikiso Kenkyujo Known dyes described in the catalog published in 1995 and in the catalog of laser coloring substances published by Exciton Inc. in 1989 and patents can be used for this purpose.

(B) Organometallic compounds containing hydrolyzable functional groups and partial condensates of these organometallic compounds

It is also preferable to use an organometallic compound containing a hydrolyzable functional group to provide a film cured after film formation by a sol-gel reaction as a matrix for the high refractive index layer used in the present invention.

Organometallic compounds include compounds composed of Si, Ti, Zr, Al, and others. Hydrolyzable functional groups include alkoxy groups, alkoxycarbonyl groups, halogen atoms and hydroxyl groups. Particular preference is given to alkoxy groups such as methoxy, ethoxy, propoxy, butoxy. Preferable organometallic compounds include organosilane compounds represented by the following formula (A0) and their partial hydrolyzates (partial condensates). Furthermore, it is well known that the organosilane represented by the formula (A0) is easily hydrolyzed and causes dehydration and subsequent condensation.

Formula (A0): (R ^a ) _α Si(X ₁ ) _4-α

In formula (A0), R ^a represents a substituted or unsubstituted aliphatic group having 1-30 carbon atoms or an aryl group having 6-14 carbon atoms. X ₁ represents a halogen atom (chlorine atom, bromine atom, etc.), an OH group, an OR ^b group, and an OCOR ^b group. In the formula, R ^b represents a substituted or unsubstituted alkyl group. α represents an integer from 0 to 3, preferably 0, 1 or 2, especially preferably 1. However, when α is 0, X represents an OR ^b group or an OCOR ^b group.

In formula (A0), the aliphatic group of R ^a is preferably those aliphatic groups with 1-18 carbon atoms, for example, (methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, decyl, dodecyl, hexadecyl, octadecyl, benzyl, phenethyl, cyclohexyl, cyclohexylmethyl, hexenyl, decenyl and dodecenyl). Those having 1 to 12 carbon atoms are more preferred, and those aliphatic groups having 1 to 8 carbon atoms are particularly preferred. The aryl group of R ^a is phenyl, naphthyl and anthracenyl, among which phenyl is preferred.

The substituents that can be used in the present invention are not particularly limited, and are preferably halogen groups (such as fluorine, chlorine and bromine), hydroxyl groups, mercapto groups, carboxyl groups, epoxy groups, alkyl groups (such as methyl, ethyl, isopropyl, propyl, butyl and tert-butyl), aryl (such as phenyl and naphthyl), aromatic heterocyclic (such as furilyl, pyrazolyl and pyridyl), alkoxy (such as methoxy, ethoxy, iso propoxy and hexyloxy), aryloxy (such as phenoxy), alkylthio (such as methylthio and ethylthio), arylthio (such as phenylthio), alkenyl (such as vinyl and 1-propenyl), alkoxysilyl (such as trimethoxysilyl and triethoxysilyl), acyloxy (such as acetoxy and (meth)acryloyl), alkoxy Carbonyl (such as methoxycarbonyl and ethoxycarbonyl), aryloxycarbonyl (such as phenoxycarbonyl), carbamoyl (such as carbamoyl, N-methylcarbamoyl, N,N-dimethyl carbamoyl and N-methyl-N-octylcarbamoyl) and amido groups (eg acetamido, benzamido, acrylamido and methacrylamido).

Among these substituents, hydroxyl, mercapto, carboxyl, epoxy, alkyl, alkoxysilyl, acyloxy and amido groups are more preferred, epoxy, polymeric acyloxy ((meth)acrylic) groups are especially preferred acyl) and polymeric amido (acrylamido and methacrylamido). Also, these substituents may be substituted.

As mentioned above, R ^b represents a substituted or unsubstituted alkyl group, but the substituents of the alkyl group are similar to those described for R ^a .

The content of the compound represented by formula (A0) is preferably 10-80% by weight, more preferably 20-70% by weight, especially preferably 30-50% by weight, based on the total solid content of the high refractive index layer.

The compound represented by the formula (A0) is, for example, those described in paragraphs [0054] to [0056] of JP-A-2001-166104.

In the high refractive index layer, the organic binder preferably has a silanol group. A binder having a silanol group is preferable because the silanol group can further improve the physical strength, chemical resistance, and weather resistance of the high-refractive index layer. The silanol group can be added to the adhesive by, for example, combining an organosilane compound having a crosslinking or polymerizing functional group represented by formula (A0) with a coating compound, and an adhesive precursor (curing polyfunctional mono body and polyfunctional oligomer), a polymerization initiator, and a dispersant contained in a dispersion liquid of high refractive index inorganic fine particles are mixed, and as a compound forming a binder of a coating compound constituting a high refractive index layer, the The coating compound is coated on the transparent protective film, and then the dispersant, polyfunctional monomer, polyfunctional oligomer, and organosilane compound represented by formula (A0) are crosslinked or polymerized.

The hydrolysis and condensation reactions of the solidified organometallic compound are preferably carried out in the presence of a catalyst. Catalysts include inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid; organic acids such as oxalic acid, acetic acid, formic acid, trifluoroacetic acid, methanesulfonic acid, and toluenesulfonic acid; inorganic bases such as sodium hydroxide, potassium hydroxide, and ammonia; organic bases such as triethyl Amines and pyridines; metal alkoxides such as aluminum triisopropoxide, tetrabutoxyzirconium and tetrabutoxytitanate; and metal chelates such as β-diketones and β-ketoates. Specifically, they are compounds described in paragraphs [0071] to [0083] of JP-A-2000-275403.

The mixing ratio of these catalyst compounds is in the range of 0.01 to 50% by weight, preferably 0.1 to 50% by weight, more preferably 0.5 to 10% by weight, based on the organometallic compound. The reaction conditions should be properly controlled according to the reactivity of the organometallic compound.

In the high refractive index layer, it is preferable that the host has a specific polar group. Specific polar groups include anionic groups, amino groups, and quaternary ammonium groups. Specifically, these anionic groups, amino groups and quaternary ammonium groups are similar to those used in dispersants.

The matrix of the high-refractive index layer having a specific polar group is obtained, for example, by mixing a dispersion liquid containing high-refractive-index inorganic fine particles and a dispersant with a coating compound for the high-refractive index layer, and The composition of the binder precursor (curing multifunctional monomer and multifunctional oligomer with specific polar groups) is mixed with a polymerization initiator as a curing film-forming compound, and then mixed with at least any formula (A0) represented An organosilane compound having a specific polar group and also having a crosslinking or polymerizing functional group, and, if necessary, mixing a monofunctional monomer having a specific polar group and a crosslinking or polymerizing functional group, coating the coating compound onto the transparent protective film, thereby crosslinking or polymerizing the above-mentioned dispersant, monofunctional monomer, polyfunctional monomer, polyfunctional oligomer and/or organosilane compound represented by formula (A0).

A monofunctional monomer having a specific polar group can facilitate the dispersion of inorganic fine particles in the coating compound and is thus preferable. Moreover, after coating, the binder is obtained by crosslinking or polymerizing the monofunctional monomer with the dispersant, polyfunctional monomer and polyfunctional oligomer, whereby the inorganic fine particles are preferably and uniformly dispersed in the high refractive index layer In order to provide a high refractive index layer excellent in physical strength, chemical resistance and weather resistance.

The monofunctional monomer having an amino group or a quaternary ammonium group is preferably used at 0.5 to 50% by weight, more preferably 1 to 30% by weight, based on the dispersant. If the binder is formed by crosslinking or polymerization simultaneously with and after the coating of the high-refractive index layer, the monofunctional monomer is effectively made to function before the coating of the high-refractive index layer.

Also, the matrix of the high refractive index layer of the present invention corresponds to the organic binder (B), including cured and formed organic polymers containing well-known conventional crosslinking or polymerizing functional groups. It is preferable that the matrix has a structure in which the polymer is further crosslinked or polymerized after the high refractive index layer is formed. Such polymers include, for example, polyolefins (made from saturated hydrocarbons), polyethers, polyureas, polyurethanes, polyesters, polyamines, polyamides, and melamine resins. Among them, polyolefins, polyethers, and polyureas are preferable, and polyolefins and polyethers are more preferable. The weight average molecular weight of the organic polymer before curing is preferably 1×10 ³ to 1×10 ⁶ , more preferably 3×10 ³ to 1×10 ⁵ .

It is preferable that the organic polymer before curing is a copolymer having a repeating unit of a specific polar group similar to that in the specification and a repeating unit with a crosslinked or polymerized structure. Based on the total repeating units, the repeating units with anionic groups in the polymer are preferably 0.5-99% by weight, more preferably 3-95% by weight, most preferably 6-90% by weight. A repeating unit may have two or more different or similar anionic groups.

When a repeating unit containing a silanol group is included, the proportion thereof is preferably 2-98 mol%, more preferably 4-96 mol%, most preferably 6-94 mol%. When amino group-containing or quaternary ammonium group-containing repeating units are included, the proportion thereof is preferably 0.1 to 50% by weight, more preferably 0.5 to 30% by weight.

Similar effects can be obtained when silanol groups, amino groups, and quaternary ammonium groups are contained in the repeating unit having an anionic group or the repeating unit having a crosslinked or polymerized structure.

The repeating unit having a cross-linked or polymerized structure in the polymer is preferably 1-90% by weight, more preferably 5-80% by weight, most preferably 8-60% by weight.

The matrix made of a cross-linked or polymerized binder is preferably formed by coating a high-refractive-index layer-forming compound on a transparent protective film, and performing cross-linking or polymerization simultaneously with or after the coating.

(Other compounds for high refractive index layer)

The high refractive index layer used in the present invention may have any other compound depending on its application and purpose. For example, when a low-refractive-index layer is provided on a high-refractive-index layer, it is preferable that the high-refractive-index layer has a higher refractive index than the transparent protective film. Since the high refractive index layer contains halogenated elements (eg, Br, I, and Cl) and atoms such as S, N, and P other than aromatic rings and fluorine, the organic compound has a higher refractive index. Therefore, an adhesive obtained by crosslinking or polymerizing a curing compound having these elements or atoms can also be preferably used.

In addition to these compounds (inorganic fine particles, polymerization initiators, and sensitizers), the high-refractive index layer may have resins, surfactants, antistatic agents, coupling agents, thickeners, color protectants, colorants ( pigments and dyes), defoamers, leveling agents, flame retardants, ultraviolet absorbers, infrared absorbers, viscosity imparting agents, polymerization inhibitors, antioxidants, surface modifiers, and conductive metal fine particles.

[Formation of high refractive index layer]

It is preferable to form the high-refractive-index layer directly or via another layer on a transparent protective film described later by coating a solution of the above-mentioned compound for the high-refractive-index layer. The coating liquid usable for the high refractive index layer of the present invention is prepared by mixing and diluting an inorganic fine particle dispersion, a matrix binder solution and, if necessary, additives with a coating dispersion medium.

The coating liquid is preferably filtered before coating. At the time of filtration, it is preferable to use a filter with as small a pore diameter as possible as long as the compound of the coating liquid is not removed. The absolute filtration accuracy of the filter used for filtration is preferably 0.1-100 μm, more preferably 0.1-25 μm. Also preferred is a thickness of 0.1-10 mm, more preferably 0.2-2 mm. In this case, the filtration pressure is preferably 15 kgf/cm ² or less, more preferably 10 kgf/cm ² or less, and particularly preferably 2 kgf/cm ² or less. There are no particular restrictions on the filter elements as long as they do not affect the coating liquid. Specifically, they include filter elements similar to those used to filter wet dispersions of inorganic compounds. It is also preferred that the filtered coating solution be subjected to ultrasonic dispersion immediately before coating to effectively remove foam and maintain better dispersion.

The high refractive index layer of the present invention is coated by known film forming methods such as dip coating, air knife coating, curtain coating, roll coating, wire rod coating, gravure coating, micro gravure coating and extrusion coating , is prepared by coating the above-mentioned compound for forming a high-refractive index layer on a transparent protective film described later, and subjecting the resultant to drying and exposure to light and/or heat. Exposure to light is preferred due to faster curing. More preferably heat treatment is provided in the second half of the photocuring process.

Any light in the ultraviolet region or near-infrared region can be used as a light source for radiation, and the light source for ultraviolet light includes mercury vapor lamps (any of ultra-high pressure, high pressure, medium pressure or low pressure lamps), chemical lamps, carbon arc lamps, metal halide lamps, etc. lamps, xenon lamps and sunlight. It is acceptable to convert any available laser source in the wavelength range 350-420 nm into a multi-beam source for radiation. Also, the near-infrared light source includes a halogen lamp, a xenon lamp, or a high-pressure sodium lamp. It is also acceptable to convert any available laser source with a wavelength of 750-1400 nm into a multi-beam source for radiation. When a near-infrared light source is used, it may be mixed with an ultraviolet light source, or radiation may be supplied from the plane of the transparent protective film opposite to the plane on which the high-refractive index layer is coated. This treatment allows the curing of the film to proceed smoothly in the thickness direction of the coating near its surface, thereby providing a uniformly cured film state.

Photoradical polymerization can be performed by radiation in air or inert gas. In this case, it is preferable to carry out the polymerization by reducing the induction period for polymerizing the radically polymerizable monomer, or keeping the oxygen concentration at the lowest possible level sufficient to increase the polymerization rate. The ultraviolet rays are preferably incident on the surface of the coated film at an intensity of 0.1-100 mW/cm ² , and also preferably at a radiation amount of 100-1000 mJ/cm ² . It is also preferred to provide the coating film with as uniform a temperature distribution as possible during the irradiation. The temperature distribution difference is preferably controlled within ±3°C, more preferably within ±1.5°C. The above-mentioned range is preferable because the polymerization proceeds uniformly in the film thickness direction along the surface of the coated film.

According to JIS K-5400, the hardness of the pencil hardness test of the high refractive index layer is preferably H or more, more preferably 2H or more, most preferably 3H or more. The Taber test was performed according to JIS K-5400 by using a test piece on which a high refractive index layer was coated before and after the test. In terms of the scratch resistance of the high-refractive index layer, it is preferable to wear the test piece as little as possible. A high-refractive-index layer with reduced haze is more preferred. Specifically, the haze is preferably 5% or less, more preferably 3% or less, and especially preferably 1% or less.

The thickness of the high refractive index layer is preferably 30-500 nm, more preferably in the range of 50-300 nm. When the high refractive index layer is also used as the hard coat layer, the thickness is preferably 0.5-10 μm, more preferably 1-7 μm, and especially preferably 2-5 μm.

(medium refractive index layer)

As explained above, in the case where the antireflection film is composed of at least three layers, the high-refractive index layer is preferably a laminated structure composed of two layers having different refractive indices from each other. That is, it is preferable to use a transparent protective film, the lower refractive index layer (medium refractive index layer) of the two high refractive index layers, the higher refractive index layer (high refractive index layer) of the two high refractive index layers, and the low refractive index layer. Laminate in the order of the highest layer (outermost layer). The medium refractive index layer has a medium refractive index between the transparent protective film and the high refractive index layer. Thus, the refractive index is related to and dependent on each refractive index layer. The medium-refractive-index layer is prepared by coating a medium-refractive-index layer-forming compound, similarly to the preparation of the high-refractive-index layer.

Materials for preparing the middle refractive index layer of the present invention may include any known conventional materials, and are preferably those used in the preparation of high refractive index thin layers. The refractive index can be easily adjusted according to the type and amount of inorganic fine particles, and similarly to that described in the high refractive index layer, a layer is formed with a thickness of 30 to 500 nm. The thickness of this layer is more preferably 50-300 nm.

(hard coat)

A hard coat layer may be provided on the surface of the transparent protective film to impart physical strength to the antireflection film. It is particularly preferable to provide a layer between the transparent protective film and the high refractive index layer.

The hard coat layer is preferably formed by crosslinking or polymerizing photocurable and/or thermosetting compounds. The layer can be formed, for example, by coating the compound on a transparent protective film and having a compound containing polyester (meth)acrylate, urethane (meth)acrylate, polyfunctional monomer, polyfunctional oligomer, or Hydrolyzing the functional organometallic compound and crosslinking or polymerizing the resulting cured compound.

A preferred curing functional group is a photopolymerizable functional group, and a preferred organometallic compound containing a hydrolyzable functional group is an organoalkoxysilyl compound. Examples include those having a content similar to that of a matrix binder having a high refractive index layer.

The hard coat layer contains inorganic fine particles having an average primary particle diameter of 300 nm or less, preferably 10-150 nm, more preferably 20-100 nm. In this case, the average particle diameter is a weight average particle diameter. Keeping the average particle diameter of primary particles at 200 nm or less can provide a hard coat layer that has no influence on transparency. The inorganic fine particles can increase the hardness of the hard coat layer and also maintain the curing and condensation of the coating layer. In addition, these particles are also added in order to control the refractive index of the hard coat layer. Specifically, the compounds used in the configuration of the hard coat layer include compounds described in JP-A-2002-144913, JP-A-2000-9908 and WO0/46617. In the hard coat layer, the content of the fine inorganic particles is preferably in the range of 10 to 90% by weight, more preferably 15 to 80% by weight, based on the total weight of the hard coat layer.

As explained above, a high refractive index layer is also used as a hard coat layer. When using the high refractive index layer as the hard coat layer, it is preferable to form the hard coat layer by finely dispersing inorganic fine particles and incorporating them into one layer similarly to the preparation of the high refractive index layer. The thickness of the hard coat can be properly adjusted according to the application. Specifically, the thickness of the hard coat layer is preferably 0.2-10 μm, more preferably 0.5-7 μm, especially preferably 0.7-5 μm.

In the pencil hardness test according to JIS K-5400, the hardness of the hard coat layer is preferably H or greater, more preferably 2H or greater, most preferably 3H or greater. When the test piece of this layer was subjected to the Taber test according to JIS X-5400, it was shown that the abrasion was less before and after the test, confirming that the scratch resistance of the hard coat layer was better.

(low refractive index layer)

In view of imparting antireflection properties, the refractive index of the low-refractive index layer of the present invention is preferably in the range of 1.31-1.48.

It is preferable that the low refractive index layer of the present invention is provided as the outermost layer having scratch resistance and stain resistance. The low-refractive index layer is a layer with a refractive index of 1.17-1.37, which contains at least one inorganic fine particle with a hollow structure whose average particle diameter is 30%-100% of the thickness of the low-refractive index layer. The use of such inorganic fine particles for the low refractive index layer can reduce the rise in the refractive index of the layer and achieve low refractive index and high film strength, while providing no limitation to long-time thermal curing or saponification of the polarizing sheet.

[Raw material of cured film forming low refractive index layer]

In order to provide a low refractive index, effectively impart sliding properties to the surface, and greatly improve scratch resistance, it is also preferable to use a cured film-forming material in which known conventional polysiloxanes and/or fluorine-containing compounds are properly used for the above-mentioned low in the refractive index layer. More preferably, fluorine-containing compounds are added to the feedstock. It is particularly preferred that the low-refractive index layer of the present invention is formed mainly of thermally cured and/or light or radiation (eg, ionizing radiation)-cured and contains a crosslinked fluorine compound, and is composed of a fluorine-containing curable polymer.

For the above purpose, it is preferable that the low refractive index layer of the present invention is a cured film formed by applying a curing compound for forming a low refractive index layer and subjecting the resultant to a curing process, the curing compounds each containing at least one Organosilane hydrolyzates and/or their partial condensates and fluorine-containing polymers having curing reactive groups represented by formula (A3) shown below and produced in the presence of the above-mentioned inorganic fine particles and an acid catalyst.

Formula (A3): (R ^c ) _m Si(X) _4-m

(wherein R ^c represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, X represents a hydroxyl group or a hydrolyzable group. β represents an integer of 1-3)

More preferably, the low-refractive-index layer-forming compound also has a polyfunctional polymer compound having at least two or more polymer groups selected from radical polymerizable groups and/or cationic polymerizable groups, and a polymerization initiator. Later in this specification, the curing compound for forming the low refractive index layer will be described.

[Composition for forming low refractive index layer]

(inorganic fine particles with hollow structure)

The above-mentioned low refractive index layer is characterized in that it uses hollow inorganic fine particles (also referred to as hollow particles hereinafter in this specification) to further reduce the elevated refractive index of the layer. The refractive index of the hollow particles is 1.17-1.37, preferably 1.17-1.35. In this case, the refractive index represents the refractive index of the entire particle, and should not be interpreted as representing only the refractive index of the shell constituting the hollow particle. In order to increase the void ratio to further reduce the refractive index of hollow particles, the shell will be thinned and lead to a decrease in the strength of the particles. Therefore, it is necessary to maintain the refractive index of the hollow particles at 1.17 or more in view of scratch resistance.

The refractive index of these hollow particles can be measured using an Abbe refractometer [Atago Co., Ltd.].

When ri represents the radius of the void of the inorganic fine particle, and ro represents the radius of the particle shell, the void ratio w (%) of the hollow particle is calculated according to the following formula (V):

w＝(4πr _i ³ /3)/(4πr _o ³ /3)×100

The void ratio of the hollow particles is preferably 10-60%, more preferably 20-60%, most preferably 30-60%.

The average particle diameter of the hollow inorganic fine particles is preferably 30% to 100%, more preferably 35% to 80%, even more preferably 40% to 60%, of the thickness of the low refractive index layer. That is, when the thickness of the low refractive index layer is 100 nm, the particle size of the hollow particles may be 30 nm-100 nm, preferably 35 nm-80 nm, more preferably 40 nm-60 nm. When the average particle diameter falls within the above-mentioned range, sufficient strength is imparted to the film, and thus it is preferable.

Inorganic fine particles usable for the low refractive index layer include fluorine particles containing silicon dioxide (silica) and particles such as magnesium fluoride, calcium fluoride, and barium fluoride particles. Particular preference is given to silicon dioxide (silica) particles.

The inorganic fine particles are preferably in the shape of rice grains, spheres, cubes, spindles, short fibers, rings, or amorphous shapes.

(small particle size inorganic fine particles)

It is also preferred to combine at least one fine inorganic particle with an average particle diameter smaller than 25% of the thickness of the low-refractive index layer (hereinafter referred to as small-diameter fine inorganic particles in this specification) and large-diameter inorganic fine particles (hereinafter referred to as this specification) Inorganic fine particles necessary for the invention are also referred to as large-diameter inorganic fine particles) are mixed and used. Small-diameter fine inorganic particles are preferred because they do not have a hollow structure.

Since small-diameter inorganic fine particles can be sandwiched between large-diameter inorganic fine particles, it is preferable to add them and effectively function as a retaining agent for large-diameter inorganic fine particles. They are also cost effective.

When the thickness of the low refractive index layer is 100 nm, the average particle size of the small-sized inorganic fine particles is preferably between 1 nm-20 nm, more preferably between 5 nm-15 nm, particularly preferably between 10 nm-15 nm.

The small-diameter fine inorganic particles are used in an amount of preferably 5-100 parts by weight, more preferably 10-80 parts by weight, based on 100 parts by weight of the large-diameter fine inorganic particles (hollow particles).

Specific compounds include those used in hollow particles, silicon oxides being particularly preferred.

(dispersion of inorganic fine particles)

The above-mentioned hollow inorganic fine particles and small particle size inorganic fine particles can be subjected to physical surface treatment such as plasma irradiation and corona discharge treatment, or chemical surface treatment by surfactant or coupling agent, to be used for forming the low refractive index layer stable dispersion in a dispersion or solution of a cured compound, or to increase its affinity or binding with a binder compound. Particular preference is given to using coupling agents. Preferred coupling agents include alkoxy metal compounds (eg, titanium coupling agents, silane coupling agents). Treatment with a silane coupling agent is particularly preferred.

The above-mentioned coupling agent is used as a surface treatment agent for inorganic fine particles of the low refractive index layer to provide preliminary surface treatment, and then a curing compound solution is prepared. In this case, it is preferable that the coupling agent is added as an additive and added to the layer when preparing the coating liquid.

It is also preferable to disperse the inorganic fine particles in the medium in advance, and then perform the surface treatment to reduce the load of the surface treatment.

In consideration of obtaining better transparency and higher strength of the film, based on 100 parts by weight of all the compounds of the above-mentioned low refractive index layer, the above-mentioned inorganic fine particles are preferably mixed in 5-90 parts by weight, more preferably 20-60 parts by weight. Also, when the hollow particles are mixed with other particles, the hollow particles in all the particles are preferably 5-95 parts by weight, more preferably 10-90 parts by weight, and especially preferably 30-80 parts by weight.

(fluoropolymer)

As explained above, it is preferred that the low refractive index layer of the present invention is mainly made of a fluorine compound that is curable by heat and/or curable by light or radiation (for example, ionizing radiation) and that contains a crosslinkable group, and is composed of fluorine-containing Cured polymer composition.

Fluorine-containing polymers include those compounds described in the antireflection film described in Embodiments 1 to 4 of the present invention and are preferably used for this purpose.

Preferred embodiments of the fluoropolymer are those represented by the following formula (8):

In formula (8), compound [F] represents the following compound (pf1), compound (pf2) or compound (pf3).

In the compound (pf1), R ₁ represents a F atom or a perfluoroalkyl group having 1-3 carbon atoms.

In the compound (pf1)), _R3 and _R4 can be different from each other or the same, respectively represent a fluorine atom and _{a -CjF2j +1} group, wherein j represents an integer of 1-4 (j preferably represents 1 or 2) . a represents an integer of 0 or 1, and b represents an integer of 2-5. C stands for 0 or 1. When a and/or c are 0, they each represent a single bond.

In compound (pf3), R ₅ and R ₆ each represent a fluorine atom and a -CF ₃ group. a represents 0 or 1, and is the same as the above-mentioned compound (pf2). d represents an integer of 0 or 1, e represents an integer of 0 or 1-4, f represents 0 or 1, and g represents an integer of 0 or 1-5. When d, e, f and/or g are 0, they represent single bonds. Also, (e+f+g) is an integer of 1-6.

In formula (8), B represents a coupling group having 1-10 carbon atoms, more preferably 1-6, especially preferably 2-4, and it can be a straight-chain structure, a branched structure or a ring structure. Also, B may have a heteroatom selected from O, N or S. Preferred examples of the coupling group B include ^* -(CH ₂ ) ₂ -O- ^** , ^* -(CH ₂ ) ₂ -O-NH- ^** , ^* -(CH ₂ ) ₄ -O- ^** , ^* -(CH ₂ ) ₆ -O- ^** , ^* -(CH ₂ ) ₂ -O-(CH ₂ ) ₂ -O- ^** , ^* -CONH-(CH ₂ ) ₃ -O- ^** , ^* -CH ₂ CH(OH)CH ₂ -O- ^** and ^* -CH ₂ CH ₂ OCONH(CH ₂ ) ₃ -O- ^** (where ^* represents the coupling position of the polymer main chain, ^** represents (form group) the coupling position of the acryloyl group). u stands for 0 or 1.

In formula (8), X ₃ represents a hydrogen atom or a methyl group. In view of curing reaction, hydrogen atoms are preferred.

Also, in formula (8), A represents a repeating unit induced from any given vinyl monomer. A is not particularly limited as long as it is a compound constituting a monomer that can be copolymerized with a monomer corresponding to compound [F], and can be selected according to, for example, adhesiveness with the lower layer, Tg of the polymer (useful for film hardness), ), the factors of solubility with solvent, transparency, sliding properties, dust resistance and stain resistance are freely selected. Also, A can be formed with single or multiple vinyl monomers.

Preferred examples of A include vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, t-butyl vinyl ether, cyclohexyl vinyl ether, isopropyl vinyl ether, hydroxyethyl vinyl ether, hydroxy Butyl vinyl ether, vinyl glycidyl ether, allyl vinyl ether; vinyl esters such as vinyl acetate, vinyl propionate and vinyl butyrate; (meth)acrylates such as (meth) Methyl acrylate, ethyl (meth)acrylate, hydroxyethyl (meth)acrylate, glycidyl methacrylate, allyl (meth)acrylate, (meth)acryloxypropyltrimethoxy Silanes; styrene derivatives such as styrene and p-hydroxymethylstyrene; unsaturated carboxylic acids such as crotonic acid, maleic acid and itaconic acid and their derivatives. Vinyl ether derivatives and vinyl ester derivatives are more preferred, and vinyl ether derivatives are especially preferred.

x, y and z represent mol% of the respective compounds, or represent values satisfying 30≤x≤60, 5≤y≤70 and 0≤z≤65. The preferred situation of A is 35≤x≤55, 30≤y≤60 and 0≤z≤20, and the particularly preferred situation is 40≤x≤55 and 40≤y≤55 and 0≤z≤10, however, the precondition It is x+y+z=100.

Particular preference is given to those compounds in which the [F] compound in formula (8) represents the (pf1) compound. Examples are compounds described in paragraphs [0043] to [0047] of JP-A-2004-45462.

(organosilane compound)

The organosilane represented by formula (A3) has the same meaning as the organosilane represented by formula (A).

Detailed examples are also described below.

R ₇ : hydrogen atom or methyl group v: an integer of 2-4

R _g : methyl or ethyl

As explained above, the curing compound forming the low-refractive index layer may also have a polyfunctional polymer compound.

The polyfunctional polymeric compound may contain two or more polymeric groups in the form of radically polymerizable functional groups and/or cationic polymerizable functional groups. The radical polymerizable functional group includes unsaturated alkenyl groups such as (meth)acryloyl, vinyloxy, styryl and allyl, preferably (meth)acryloyl. It is preferred that the curing compound contains a polyfunctional monomer containing 2 or more radically polymerizable groups therein.

The radically polymerizable polyfunctional monomer containing a radically polymerizable group is preferably selected from compounds having at least two terminal ethylenically unsaturated bonds. Compounds having 2 to 6 terminal ethylenically unsaturated bonds in the molecule are preferred. These compounds are well known in the polymer raw material industry. This compound can be used in the present invention without any limitation. They are available in chemical form, for example, monomers, prepolymers (dimers, trimers) and oligomers, or in mixtures and copolymers.

The cationic polymerizable compound used in the present invention may include any compound that undergoes polymerization and/or crosslinking by irradiation of active energy rays in the presence of a cationic polymerization initiator sensitive to active energy rays. As typical examples, there are epoxy compounds, cyclic sulfide compounds, cyclic ether compounds, spiroorthoester compounds, vinyl hydrocarbon compounds and vinyl ether compounds. One kind or two or more kinds of such cationic polymerizable organic compounds can be used in the present invention. Cationic polymerizable group-containing compounds having 2 to 10 cationic polymerizable groups in one molecule are preferred, and those compounds having 2 to 5 groups in one molecule are particularly preferred. Specifically, these radical polymerizing compounds and cation polymerizing compounds, compounds similar to those of the polyfunctional monomers and oligomers in the case of the high refractive index layer.

Based on the weight ratio of the radical polymerizable compound to the cationic polymerizable compound, the content ratio of the radical polymerizable compound to the cationic polymerizable compound is preferably 90:10-20:80. A more preferred ratio is 80:20-30:70. It is also preferred that a polyfunctional polymeric compound containing a radical polymerizable compound and a cationic polymerizable compound be mixed in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the fluorine-containing polymer.

(other additives)

Preferably, in addition to the above-mentioned compounds, the low-refractive index layer of the present invention may have an antifouling agent and a smoothing agent (known polysiloxane compound or fluorine compound) for imparting stain resistance, water repellency, if necessary resistance, chemical resistance and sliding properties. These additives are preferably added in an amount of 0.01 to 20% by weight, more preferably 0.05 to 10% by weight, and especially preferably 0.1 to 5% by weight, based on the total curable compound forming the low-refractive index layer.

Preferred polysiloxane compounds include but are not limited to the following compounds: "X-22-174DX", "X-22-2426", "X-22-164b", "X22-164C", "X-22-170DX ", "X-22-176D" and "X-22-1821" [trade name: Shin-Etsu Chemical Co., Ltd.]; "FM-0725", "FM-7725", "DMS-U22", "RMS-033", "RMS-083" and "UMS-182" [trade name: Chisso Corporation].

Preferred fluorine compounds are those containing fluoroalkyl groups. The fluoroalkyl groups are preferably those having 1 to 20 carbon atoms, more preferably those having 1 to 10 carbon atoms. They can be linear structures [e.g., -CF ₂ CF ₃ , -CH ₂ (CF ₂ ) ₄ H, -CH ₂ (CF ₂ ) ₈ CF ₃ and -CH ₂ CH ₂ (CF ₂ ) ₄ H], branched [e.g., -CH(CF ₃ ) ₂ , -CH ₂ CF(CF ₃ ) ₂ , -CH(CH ₃ )CF ₂ CF ₃ , -CH(CH ₃ )(CF ₂ ) ₅ CF ₂ H] or Alicyclic structure (preferably 5-membered ring or 6-membered ring, for example, perfluorocyclohexyl, perfluorocyclopentyl or alkyl substituted by these groups), or may have an ether bond (for example, -CH ₂ OCH ₂ CF ₂ CF ₃ , -CH ₂ CH ₂ OCH ₂ C ₄ F ₈ H, -CH ₂ CH ₂ OCH ₂ CH ₂ C ₈ F ₁₇ and -CH ₂ CH ₂ OCF ₂ CF ₂ OCF ₂ CF ₂ H). Many fluoroalkyl groups can be contained in the same molecule.

It is preferable that the fluorine compound further has a substituent favorable for compatibility with the thin film of the low refractive index layer. These substituents may be the same or different. They can preferably be used in large amounts. Specifically, preferred substituents include acryloyl, methacryloyl, vinyl, aryl, cinnamoyl, epoxy, oxetanyl, hydroxyl, polyoxyalkylene, carboxyl and amino.

The fluorine compound may be a polymer or oligomer with a compound not containing a fluorine atom, and the molecular weight is not particularly limited. The content of fluorine atoms in the fluorine compound is not particularly limited. Its content is preferably 20% by weight or more, especially preferably 30-70% by weight, most preferably 40-70% by weight. Preferred fluorine compounds include but are not limited to "R-2020", "M-2020", "R-3833" and "M-3833" [trade name: Daikin Industries Ltd.]; "Megafack F-171", "Megafack F -172", "Megafack F-179A", or "DefensaMCF-300" [trade name; Dainippon Ink and Chemicals Inc.].

For the purpose of imparting dust-removing and antistatic properties to the low-refractive index layer, a known cationic surfactant, or a dust-removing agent and an antistatic agent (polyoxyalkylene compound) may be added as needed. In these dust removers and antistatic agents, the above structural units may be introduced into polysiloxane compounds or fluorine compounds as some functional groups of these compounds. These agents are preferably added in the range of 0.01-20% by weight, more preferably 0.05-10% by weight, especially preferably 0.1-5% by weight, relative to the total solids of the curing compound. Specifically, preferred compounds include, but are not limited to, "Megafack F-150" [trade name: Dainippon Ink and Chemicals Inc.] and "SH-3748" [trade name: Toray Dow Corning].

The low refractive index layer may also contain microvoids. Examples are described in JP-A-9-222502, JP-A-9-288201 and JP-A-11-6902.

The antireflection film described above in Embodiments 1 to 4 of the present invention can preferably use these additives.

In addition, preferred properties of the low-refractive index layer are as described above in the antireflection film of Embodiments 1-4 of the present invention.

[Anti-glare function (anti-glare)]

The anti-reflection film may have an anti-glare function for diffusing external light. The antiglare function is obtained by forming unevenness on the surface of the antireflection film. When the antireflection film provides an antiglare function, the antireflection film preferably has a haze of 3-50%, more preferably 5-40%, most preferably 7-20%.

Anti-glare is related to the average surface roughness (Ra). The surface unevenness is represented by the average surface roughness (Ra) calculated on the basis of a surface area of 1 mm ² randomly collected from an area of 100 cm ² . The average surface roughness is preferably 0.01-0.4 μm, more preferably 0.03-0.3 μm, even more preferably 0.05-0.25 μm, especially preferably 0.07-0.2 μm.

The average surface roughness (Ra) was measured in accordance with JIS B-0601-1994.

The antireflection film of the present invention can determine the configuration of surface unevenness using an atomic force microscope (AFM).

The method of providing unevenness on the surface of the antireflection film may include any method as long as the configuration of the surface can be sufficiently maintained. For example, this method includes using fine particles for the low-refractive index layer to provide unevenness on the surface of the film (for example, JP-A-2000-271878); 50% by weight) added to the lower layer of the low-refractive index layer (high-refractive-index layer, medium-refractive-index layer or hard coat layer) to form a surface uneven film, thereby providing a low-refractive index layer while maintaining configuration thereon (e.g. , JP-A-2000-281410 and JP-A-2000-95893); after coating to form a low refractive index layer, by physical means, for example, embossing method (for example, JP-A-63-278839, JP-A-63-278839, JP- A-11-183710 and JP-A-2000-275401), a method of peeling coated paper transfer (for example, Patent Registration No. 3332534) and a method of particle spray transfer (for example, JP-A-6-87632) thereon Transfer of heterogeneous configurations.

When the antiglare layer is provided by adding particles to any layer of the antireflection film, the average particle diameter of the particles used for the antiglare layer is preferably in the range of 0.2 to 10 μm. In this case, the average particle diameter is the weight-average particle diameter of secondary particles (primary particles without particle aggregation). The antiglare layer particles include inorganic fine particles and organic particles. Specifically, inorganic fine particles include particles such as silica, titania, zirconia, alumina, tin oxide, ITO, zinc oxide, calcium carbonate, barium sulfate, talc, kaolin and calcium sulfate. Silica and alumina are preferred.

Preferred organic particles are resin particles. Specifically, the resin particles include particles made using polysiloxane resins, melamine resins, benzoguanamine resins, polymethylmethacrylate resins, polystyrene resins, and polyvinylidene fluoride resins. Preference is given to using particles made of melamine resins, benzoguanamine resins, polymethylmethacrylate resins and polystyrene resins. Particles made of polymethylmethacrylate resin, benzoguanamine resin and polystyrene resin are particularly preferably used.

Resin particles are preferred as the anti-glare layer particles for providing unevenness on the anti-glare layer. The average particle diameter of the particles is preferably 0.5-7.0 μm, more preferably 1.0-5.0 μm, especially preferably 1.5-4.0 μm. Furthermore, the refractive index of the particles is preferably 1.35-1.80, more preferably 1.40-1.75, even more preferably 1.45-1.75. Particles with a narrow particle size distribution are more preferred. The S value representing the particle size distribution is represented by the formula (VI) shown below, wherein the S value is preferably 2 or less, more preferably 1.0 or less, particularly preferably 0.7 or less.

Formula (VI): S=(D _0.9 -D _0.1 )/D _0.5

D _0.1 : Particle size equivalent to 10% of the integral value in terms of volume particle size

D _0.5 : Particle size equivalent to 50% of the integral value in terms of volume particle size

D _0.9 : Particle size equivalent to 90% of the integral value in terms of volume particle size

Also, translucent particles are preferred as anti-glare layer particles. Although there is no particular limitation on the refractive index, they are preferably similar to (within 0.005 in terms of difference in refractive index) or different from that of the anti-glare layer by more than 0.02. By making the refractive index of the particles similar to that of the antiglare layer, the contrast ratio when the antireflection film is fixed on the image display panel is improved. In addition, making the refractive index different between the particles and the antiglare layer allows the improvement of visibility (problems related to irregular reflection and viewing angle characteristics) that can be found when the antireflection film is fixed on the liquid crystal display panel.

When the refractive index differs between the particles and the antiglare layer, this difference is preferably 0.02-0.5, more preferably 0.03-0.4, especially preferably 0.05-0.3.

Two or more different types of translucent particles may be mixed and used as the translucent particles. When using two or more kinds of translucent particles, in order to achieve effective control of the refractive index of the mixture of multiple particles, the difference between the refractive index between the translucent particle with the highest refractive index and the translucent particle with the lowest refractive index The difference is preferably 0.02 or more to 0.10 or less, particularly preferably 0.03 or more to 0.07 or less. It is also possible to use large size translucent particles to impart anti-glare properties and use small size translucent particles to impart other optical properties. For example, when a transparent protective film coated with an antireflection film is attached to a high-precision display (133 ppi or higher), the film must be free from optical performance defects called irregular reflections. Irregular reflection is produced by the increase or decrease of pixels due to the unevenness existing on the surface of the film (imparting anti-glare) and the subsequent failure of uniform brightness, and by mixing particles that are larger than translucent particles that provide anti-glare The irregular reflection is greatly improved by using translucent particles with small diameter and different refractive index from the translucent resin used as the matrix binder.

The antiglare layer particles are preferably used in an amount of 3 to 75% by weight relative to the weight of the antiglare-imparting layer.

The antiglare-imparting particles can be added to any layers built up on the antireflection film, among which hardcoat, low-refractive-index or high-refractive-index layers are preferred, hard-coat or high-refractive-index layers are especially preferred. These particles can be incorporated into multiple layers.

(light diffusion layer)

The antireflection film of the present invention may be composed of at least a light-diffusing layer with (1) a refractive index higher than that of the transparent protective film and equivalent to the high refractive index layer of the present invention and (2) a light-diffusing layer on the transparent protective film and having a refractive index lower than that of the transparent protective film. The protective film is made of an antireflection layer sequentially laminated with a low refractive index layer.

The light-diffusing layer is prepared by dispersing at least one kind of translucent particles having an average particle diameter of 0.5-5 μm in a translucent resin or a high-refractive index layer in which the translucent particles and the translucent resin The difference in refractive index between them is 0.02-0.2, there is no surface unevenness, and the content of the translucent particles is 3-30% by weight based on the total solid of the light-scattering layer. More specifically, the translucent particles dispersed in the high refractive index layer are not larger than the film thickness of the high refractive index layer, and are dispersed in the layer to impart low reflection.

The thickness of the light-diffusing layer is usually 0.5 μm to 50 μm, preferably 1 μm to 20 μm, more preferably 2 μm to 10 μm. The refractive index of the translucent resin is preferably 1.5-2.00, more preferably 1.51-1.90, even more preferably 1.51-1.85, especially preferably 1.51-1.80. Also, when measuring the refractive index of the translucent resin, the translucent particles are not included.

The difference in refractive index between the translucent particles and the translucent resin is usually 0.02-0.20, particularly preferably 0.04-0.10. When the difference was kept at 0.20 or less, there were no defects such as whitening of the film. A difference of 0.02 or more provides an excellent light-diffusing effect and is therefore preferred. As with the refractive index, the amount of translucent particles added to the translucent resin is also important. In order to maintain the transparency of the film and obtain an excellent light-diffusing effect, the content of the translucent particles is preferably 3-30% by weight, more preferably 5-20% by weight, based on the total solids of the light-diffusing layer.

When the above translucent particles are added, the translucent particles tend to settle in the translucent resin. Therefore, inorganic fillers such as silica may be added to prevent such settling. Also, the inorganic filler is more effective in preventing the settling of translucent particles as the filler volume increases, but may affect the transparency of the light-diffusing layer. Therefore, it is preferable to add the inorganic filler having a particle diameter of 0.5 μm or less in an amount of less than 0.1% by weight of the translucent resin within this range without affecting the transparency of the light-diffusing layer.

Furthermore, the average reflectance of the antireflection film having the light-scattering layer of the present invention in the wavelength range of 380nm-680nm is preferably 2.5% or less, and the haze is also preferably 10-40%. More preferably, the average reflectance is 1.8% or less and the haze is 10-35%.

The optical characteristics of the anti-reflection film can be limited within the above-mentioned range, thereby providing increased visibility without whitening of the image surface or blurred image display, sufficiently preventing a decrease in contrast or a change in color tone due to a change in viewing angle, and realizing the absence of external Higher-quality image display of reflection of light or irregular reflection of the image surface, and excellent anti-reflection properties.

According to the detailed description of translucent particles, matrix and other additives used in the light-scattering layer of the present invention, the same description can be made for the above-mentioned high-refractive index layer and anti-glare layer.

[other layers]

[Transparent antistatic layer]

In the present invention, a transparent antistatic layer containing a conductive material may be provided between the transparent protective film and the above-mentioned light-diffusing layer, which is preferable because of its preventive effect against static charges on the surface of the anti-reflection film. When fixing a polarizing plate on the observation side to prevent external surface energy on a liquid crystal display device based on IPS mode or VA mode, it is preferable to provide a conductive layer as a transparent antistatic layer.

The transparent antistatic layer can be formed by a well-known conventional method, for example, coating a coating liquid for a conductive antistatic layer containing conductive fine particles and an active curing resin; forming a conductive polymer cured film and using a transparent film-forming metal or metal Oxide provides a conductive film by evaporation or sputtering. The transparent antistatic layer may be directly formed on the transparent protective film, or the transparent antistatic layer may be formed on the transparent protective film through a primer layer that strengthens adhesion with the transparent protective film.

It is also possible to use a transparent antistatic layer as part of the antireflection film. In this case, even a thin layer can provide sufficient antistatic effect when applied in a layer relatively close to the outermost surface. There is no particular limitation on the coating method, and the most suitable coating method can be selected from known methods such as roll coating, gravure coating, wire rod coating and extrusion coating, and can be selected according to the coating used for the resistance. The characteristics and coating amount of the coating solution for the electrostatic layer are used.

Transparent antistatic layers can be prepared by suitably adapting known conventional antistatic layers. The transparent antistatic layer includes, for example, "Status of prospect of transparent electric conductive films" edited by the Research Department, Toray Research Center Inc., "New development of transparent electric conductive films" edited by Yutaka Toyoda, published by Toray Research Center Inc. in 1997 and those described in the literature published by CMC in 1999.

Also, the transparent antistatic layer is preferably 0.01-10 μm, more preferably 0.05-5 μm.

The surface resistance of the transparent antistatic layer is preferably less than 2×10 ¹² Ω/□, more preferably 10 ⁵ -10 ¹² Ω/□, even more preferably 10 ⁵ -10 ⁸ Ω/□. The surface resistance of the transparent antistatic layer can be measured by a four-probe method.

Preferably the transparent antistatic layer is substantially transparent. Specifically, the haze of the transparent antistatic layer is preferably 10% or less, more preferably 3% or less, most preferably 1% or less. The light transmittance at a wavelength of 550 nm is also preferably 50% or greater, more preferably 60% or greater, even more preferably 65% or greater, most preferably 70% or greater.

It is also preferable that the surface strength of the transparent antistatic layer is excellent. Specifically, it is preferable that the hardness of the pencil hardness test with a load of 1 kg of the transparent antistatic layer (specified in JIS K-5400) is the above-mentioned H, more preferably 2H or more, most preferably 3H or more.

The transparent antistatic layer is preferably a cured resin layer containing conductive inorganic fine particles.

(conductive inorganic fine particles for transparent antistatic layer)

The specific surface area of the above-mentioned conductive inorganic fine particles is preferably 10-400 m ² /g, more preferably 30-150 m ² /g.

The conductive inorganic fine particles include, for example, Chapters 3 and 4 of "Status and prospect of transparent electric conductive films" edited by Technical Information Institute Co., Ltd. and "Development and application of electric conductive fillers" (Technical Information Institute Co., Ltd. published in 1997) described in the inorganic compound. Specifically, preferable examples are formed by using metal oxides or nitrides. Metal oxides or nitrides include, for example, tin oxide, indium oxide, zinc oxide, and titanium nitride. Particular preference is given to tin oxide and indium oxide.

The conductive inorganic fine particles may include other elements in addition to these metal oxides or nitrides as main components. The main component refers to the largest component (% by weight) among the components constituting the particles. Other elements include, for example, Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P, S, B, Nb, In, V and halogen atom. In order to improve the conductivity of tin oxide and indium oxide, Sb, P, B, Nb, In, V or halogen atoms are preferably added. Sb-containing tin oxide (ATO) and Sn-containing indium oxide (ITO) are particularly preferred. The content of Sb in ATO is preferably 3-20% by weight. The content of Sn in ITO is preferably 5-20% by weight.

The average particle diameter of primary particles of the conductive inorganic fine particles of the transparent antistatic layer is preferably 1 to 150 nm, more preferably 3 to 100 nm. The conductive inorganic fine particles of the formed transparent antistatic layer are generally 1 to 200 nm, more preferably 10 to 80 nm in terms of average particle diameter. The average particle diameter of the conductive inorganic fine particles is expressed by converting the particle weight into a weight meter, and can be measured by a light scattering method or an electron micrograph.

The conductive inorganic fine particles may be surface-treated. Surface treatment is carried out by using inorganic or organic compounds. Inorganic compounds used for surface treatment include alumina and silica. Particular preference is given to treatment with silica. Organic compounds useful for surface treatment include polyols, alkanolamines, stearic acid, silane coupling agents, and titanate coupling agents. Most preferred are silane coupling agents. Two or more compounds can be used in combination for surface treatment.

The conductive inorganic fine particles are preferably granules, spheres, cubes, spindles or amorphous. Two or more conductive inorganic fine particles may be mixed for the antistatic layer.

The content of the conductive inorganic fine particles in the transparent antistatic layer is preferably 20-90% by weight, more preferably 25-85% by weight, even more preferably 30-80% by weight.

(Adhesive for transparent antistatic layer)

Crosslinked polymers, ie cured resins, can be used as binders in the transparent antistatic layer. The crosslinked polymer preferably has anionic groups. In the polymer having a crosslinked anionic group, the main chain of the polymer having an anionic group is preferably a crosslinked structure. The anionic group has the function of keeping the conductive inorganic fine particles dispersed. The cross-linked structure has the function of imparting film-forming ability to the polymer, thereby strengthening the transparent antistatic layer.

Polymer backbones include polyolefins (saturated hydrocarbons), polyethers, polyureas, polyurethanes, polyesters, polyamines, polyamides, and melamine resins. Polyolefin, polyether and polyurea backbones are preferred. Most preferred are polyolefin backbones.

The main chain of polyolefin is composed of saturated hydrocarbons, and is produced by, for example, addition polymerization of unsaturated polymerizing groups. The main chain of polyether belongs to repeating units bonded by ether linkages (-O-), and can be produced by, for example, ring-opening polymerization of epoxy groups. The main chain of polyurea belongs to repeating units bonded by urea bonds (-NH-CO-NH-), and is produced by, for example, condensation polymerization of isocyanate groups and amino groups. The main chain of polyurethane belongs to repeating units bonded by urethane bonds (-NH-CO-O-), and is produced by, for example, condensation polymerization of isocyanate groups and hydroxyl groups (including N-methylol). The main chain of polyester belongs to repeating units bonded by ester bonds (-CO-O-), and is produced by, for example, condensation polymerization of carboxyl groups (including acyl halides) and hydroxyl groups (including N-methylol). The main chain of polyamines consists of repeating units bonded by imino linkages (-NH-) and is prepared by, for example, ring-opening polymerization of piperazine groups. The main chain of the polyamide belongs to repeating units bonded by an amide bond (-NH-CO-), and is produced by, for example, the reaction of an isocyanate group with a carboxyl group (including acyl halide). The main chain of the melamine resin itself belongs to a crosslinked structure, and is produced by, for example, condensation polymerization of a triazine group (eg, melamine) and an aldehyde (eg, formaldehyde).

The anionic group can be directly bonded to the main chain of the polymer, or bonded to the main chain through a coupling group. The anionic group is preferably bonded to the main chain through a coupling group and acts as a side chain.

Preferable examples of the anionic group include a carboxylic acid group (carboxyl group), a sulfonic acid group (sulfo group), and a phosphoric acid group (phosphono group). Preference is given to sulfonic acid groups and phosphoric acid groups.

Anionic groups can be used in the form of salts. The cations forming the anionic groups are preferably alkali metal ions. Also, the protons of the anionic groups can be dissociated.

The coupling group bonded to the anionic group and the main chain of the polymer is preferably a divalent group selected from -CO-, -O-, an alkylene group, an arylene group, and combinations thereof.

The cross-linking structure is used to form chemical bonds (preferably covalent bonds) with two or more main chains, preferably covalent bonds with three or more main chains. The crosslinking structure is preferably a divalent or polyvalent group selected from -CO-, -O-, -S-, nitrogen atom, phosphorus atom, aliphatic residue, aromatic residue, and combinations thereof.

The cross-linked polymer having an anionic group is preferably a copolymer composed of an anionic group-containing repeating unit and a cross-linked structure-containing repeating unit. The content of the repeating unit having an anionic group in the copolymer is preferably 2-96% by weight, more preferably 4-94% by weight, most preferably 6-92% by weight. The repeating unit may have two or more kinds of anionic groups. The content of the repeating unit having a crosslinked structure in the copolymer is preferably 4-98% by weight, more preferably 6-96% by weight, most preferably 8-94% by weight.

The repeating unit of the cross-linked polymer having an anionic group may have both an anionic group and a cross-linked structure. Repeating units (repeating units without anionic groups or crosslinked structures) may also be contained.

Other preferred repeating units are repeating units with amino or quaternary ammonium groups and repeating units with benzene rings. Amino groups and quaternary ammonium groups are preferred because they have the same function as anionic groups to keep inorganic fine particles dispersed. Also, amino groups, quaternary ammonium groups, and benzene rings can provide the same effects even if they are included in repeating units having an anionic group or repeating units having a crosslinked structure.

The repeating unit having an amino group or a quaternary ammonium group can be obtained by directly bonding the amino group and the quaternary ammonium group to the main chain of the polymer or by bonding them to the main chain through a coupling group. Amino groups and quaternary ammonium groups are preferably bonded to the main chain via coupling groups and serve as side chains. Amino groups and quaternary ammonium groups are preferably secondary amino groups, tertiary amino groups or quaternary ammonium groups, more preferably tertiary amino groups or quaternary ammonium groups. The group bonded to the nitrogen atom of a secondary amino group, a tertiary amino group or a quaternary ammonium group is preferably an alkyl group, more preferably an alkyl group having 1 to 12 carbon atoms. The counterion of the quaternary ammonium group is preferably a halide ion. The coupling group capable of bonding the amino or quaternary ammonium group to the main chain of the polymer is preferably a divalent group selected from -CO-, -NH-, -O-, alkylene, arylene or combinations thereof group. When the anionic group-containing crosslinked polymer has repeating units containing amino groups or quaternary ammonium groups, the content of the repeating units is preferably 0.06-32% by weight, more preferably 0.08-30% by weight, most preferably 0.1-28% by weight.

The reactive organosilicon compounds (1) to (3) described in JP-A-2003-39586 can be used in combination with these binders. Relative to the total amount of the binder and the active organosilicon compound, the amount of the active organosilicon compound is in the range of 10-100%.

Laminated antireflective films can also be provided with moisture barrier layers, antistatic layers (conductive layers), primer layers, undercoat layers, protective layers, sealing layers or sliding layers. Provides a sealing layer to block electromagnetic waves or infrared rays.

<Transparent protective film>

As explained above, the antireflection film is coated on the transparent protective film of the polarizing plate of the present invention. Transparent protective films include, for example, cellulose esters (such as triacetyl cellulose, diacetyl cellulose, propionyl cellulose, butyryl cellulose, levulinyl cellulose, and nitrocellulose), polyamide, polycarbonate Esters, polyesters (for example, polyethylene terephthalate, polyethylene naphthalate, poly-1,4-cyclohexanedimethylene terephthalate, polyethylene-1,2- Diphenoxyethane-4,4'-dicarboxylate, polybutylene terephthalate), polystyrenes (e.g. syndiotactic polystyrene), polyolefins (e.g. polypropylene, Polyethylene, polymethylpentene, polycycloalkanes), polysulfone, polyethersulfone, polyacylate, polyetherimide, polymethylmethacrylate, and polyetherketone. Preference is given to triacetylcellulose, polycarbonate, polyethylene terephthalate and polyethylene naphthalate.

The light transmittance of the transparent protective film is preferably 80% or more, more preferably 86% or more. The haze of the transparent protective film is preferably 2.0% or less, more preferably 1.0% or less. Also, the refractive index of the transparent protective film is preferably 1.4-1.7.

The antireflection film-attached polarizing plate of the present invention is preferably prepared by coating the above-mentioned antireflection film on the above-mentioned transparent protective film, and adhering a polarizing sheet to be described later on the surface opposite to the transparent protective film by an adhesive . This method can make the overall film thickness of the polarizing plate thinner, and also reduce the weight of an image display device on which the polarizing plate is fixed.

Important factors in providing preferred transparent protective films for polarizers are well-balanced hydrophobic/hydrophilic properties of the film, adhesion of the polarizer to the vinyl alcohol film and uniform optical properties over the entire film surface, particularly preferably fibrous Acylate film. Furthermore, cellulose fatty ester (cellulose acylate) films, and films containing cellulose acylate, a plasticizer and fine particles are also particularly preferred.

[Cellulose acylate film]

Preferred cellulose acylate films are those described as antireflection films in Embodiments 1 to 4 of the present invention.

Also, a preferable plasticizer in the cellulose acylate film is a plasticizer having an octanol/water partition coefficient (logP value) of 0 or 10. When the log P value of the compound is 10 or less, it is excellent in compatibility with cellulose acylate and does not cause defects such as whitening filming or dusting. When the log P value is greater than 0, the cellulose acylate film does not become excessively hydrophilic, and problems such as impairment of water repellency of the film rarely occur. Therefore, it is preferable to use the compound within the above range. As a log P value, 1 or 8 is preferred, 2 or 7 is particularly preferred.

The octanol/water partition coefficient (log P value) can be calculated by the shake flask method according to JIS Z7260-107 (2000). Also, evaluation is performed by computational chemistry or empirical methods using octanol/water partition coefficient (log P value) instead of actual measurement. Preferably by Crippen's fragmentation method [J.Chem.Inf.Comput.Sci., Vol. 27, p. 21 (1987), Viswanadhan's fragmentation method [J.Chem.Inf.Comput.Sci., Vol. 29 , p. 163 (1989)] or Broto's fragmentation method [Eur.J.Med.Chem.-Chim.Theor., Vol. 19, p. 71 (1984)] for calculation. Of these methods, Crippen's crushing method is preferred. When the log P value of a certain compound varies with the measurement method or calculation method, it is preferable to use Crippen's fragmentation to judge whether the compound is within the scope of the present invention.

<Polarizer>

[Transparent protective film]

The polarizer of the present invention has transparent protective films on both sides of the polarizer. There is no particular limitation on the type of transparent protective film, and the following films can be used for this purpose: cellulose esters such as cellulose acetate, cellulose acetate butyrate and cellulose propionate, or polycarbonate, polyolefin, Polystyrene, polyester and others. Commercially available products include, for example, "Fuji Tack" manufactured by Fuji Photo Film Co., Ltd., triacetylcellulose film of Konica Corporation, "Zeonor" of Zeon Corporation, and "Arton" of Japan Synthetic Rubber Co., Ltd. . Other products include non-birefringent optical resin materials described in JP-A-8-110402 and JP-A-11-293116.

The transparent protective film of the polarizing plate must have physical properties such as transparency, suitable moisture permeability, low birefringence and suitable rigidity, and the thickness of the film is preferably 5-500 μm, more preferably 20-200 μm, especially preferably in consideration of handling and durability 20-100μm. The aforementioned cellulose acylate film is most preferred as the transparent protective film of the present invention.

[Polarizing sheet]

The polarizing sheet of the present invention is preferably made of polyvinyl alcohol (PVA) and dichroic molecules. It is also possible to use a polyethylene polarizing sheet prepared by dehydrating and dechlorinating PVA and polyvinyl chloride to provide a polyene structure followed by orientation, as described in JP-A-11-248937.

PVA is a polymer raw material obtained by saponifying polyvinyl acetate and may contain compounds capable of copolymerization with vinyl acetate, for example, unsaturated carboxylic acids, unsaturated sulfonic acids, olefins, and vinyl ethers. Modified PVA containing acetoacetyl groups, sulfonic acid groups, carboxyl groups and alkylene oxides can also be used.

There is no particular limitation on the degree of saponification of PVA, wherein a preferable degree of saponification is 80-100 mol%, and a particularly preferable degree of saponification is 90-100 mol% in consideration of solubility and other properties. There is no particular limitation on the degree of polymerization of PVA, wherein a preferred degree of polymerization is 1,000-10,000, and a particularly preferred degree of polymerization is 1,500-5,000.

In view of enhanced durability, the syndiotacticity of PVA is preferably 55% or more, as described in Japanese Patent No. 2978219, and also preferably 45-52.5%, as described in Japanese Patent No. 3317494.

PVA is preferably formed into a film to which dichroic molecules are added to provide polarizing flakes. In general, a PVA film is preferably produced by casting a bulk solution of a PVA resin dissolved in water or an organic solvent to form a film. The polyvinyl alcohol resin is generally contained in the bulk solution at a concentration of 5-20% by weight, and the bulk solution is cast to produce a PVA film with a thickness of 10-200 μm. PVA films can be produced by referring to the methods described in Japanese Patent No. 3342516, JP-A-09-328593, JP-A-13-302817 and JP-A-14-144401.

There is no particular limitation on the crystallinity of the PVA film. A PVA film with an average crystallinity (Xc) of 50-75% by weight can be used, as described in Japanese Patent No. 3251073; and in order to reduce the change of in-plane tone, a PVA film with an average crystallinity of 38% or less can be used, As described in JP-A-14-236214.

A PVA film having a smaller birefringence (Δn) is more preferable. A PVA film having a birefringence of 1.0×10 ^-3 or less is preferred, as described in Japanese Patent No. 3342516. However, as described in JP-A-14-228835, the PVA film can have a birefringence of 0.02-0.01 to achieve higher polarization while avoiding possible cutting during stretching of the PVA film, or as described in JP-A-14 As described in -060505, (nx+ny)/2-nz can be made between 0.0003-0.01. In this case, nx represents the refractive index in the axial direction of the film, ny represents the refractive index in the film width direction, and nz represents the refractive index in the film thickness direction.

The retardation Re(in-plane) of the PVA film is preferably 0 nm to 100 nm, more preferably 0 nm to 50 nm. Also, Rth (thickness direction of the film) of the PVA film is preferably 0 nm to 500 nm, more preferably 0 nm to 300 nm.

In the polarizing plate of the present invention, a PVA film having a 1,2-ethylene glycol bonding amount of 1.5 mol% or less as described in Japanese Patent No. 3021494, and a PVA film as described in JP-A-13-316492 can be preferably used. The optical dust particles of 5 μm or more are 500 pieces or less per 100 cm ² of a PVA film having a temperature obtained from hot water of 1.5° C. or less in the TD direction of the film as described in JP-A-14-030163 A marked PVA film of a cutting temperature, or a PVA film prepared by using a solution in which a polyvalent alcohol (trivalent to hexavalent) such as glycerin is added at 1 to 100 parts by weight, or a PVA film prepared by using a solution in which a polyvalent alcohol (trivalent to hexavalent) such as glycerin is added at 1 to 100 parts by weight or The obtained PVA film was added with a solution of a plasticizer described in JP-A-06-289225.

There is no particular limitation on the thickness of the PVA film before stretching. From the viewpoint of maintaining a stable film and uniform stretching of the film, the film thickness is preferably 1 μm to 1 mm, more preferably 20 to 200 μm. As described in JP-A-14-236212, a thin PVA film which develops a stress of 10 N or less when stretched 4 to 6 times in water can also be used.

Higher iodide ions (I ₃ ⁻ or I ₅ ⁻ ) and dichroic dyes can preferably be used as dichroic molecules. The use of higher iodide ions is particularly preferred in the present invention. As described in "Application of polarizing plate" edited by Nagata R. (published by CMC) and "Kogyozairyo," Vol. 28, No. 7, pp. 39-45, by dissolving therein iodine in potassium iodide solution and/or boric acid Immersion of PVA in solution in solution can produce higher iodide ions in a state of being adsorbed to PVA and aligned.

When dichroic dyes are used as dichroic molecules, azo coloring substances are preferred, disazo and azide coloring substances are particularly preferred. Since water-soluble dichroic dyes are preferred, hydrophilic substituents such as sulfonic acid groups, amino groups, and hydroxyl groups can be introduced into the dichroic molecule. They are preferably used as free acids, alkali metal salts, ammonium salts or amine salts.

These dichroic dyes include, benzidine dyes such as C.I. Direct Red 37, Congo Red (C.I. Direct Red 28), C.I. Direct Violet 12, C.I. Direct Blue 90, C.I. Direct Blue 22, C.I. Direct Blue 1, C.I. Direct Blue 151, C.I. Direct Green 1; difenyl urea dyes such as C.I. Direct Yellow 44, C.I. Direct Red 23, C.I. Direct Red 79; stilbene dyes such as C.I. Direct Yellow 12; dinaphthylamine dyes such as C.I. Direct Red 31; J acids such as C.I. Direct Red 81, C.I. Direct Purple 9 and C.I. Direct Blue 78.

Other dichroic dyes include the following: C.I. Direct Yellow 8, C.I. Direct Yellow 28, C.I. Direct Yellow 86, C.I. Direct Yellow 87, C.I. Direct Yellow 142, C.I. Direct Orange 26, C.I. Direct Orange 39, C.1. Direct Orange 72 , C.I. Direct Orange 106, C.I. Direct Orange 107, C.I. Direct Red 2, C.I. Direct Red 39, C.I. Direct Red 83, C.I. Direct Red 89, C.I. Direct Red 240, C.I. Direct Red 242, C.I. Direct Red 247, C.I. Direct Purple 48 , C.I. Direct Purple 51, C.I. Direct Purple 98, C.I. Direct Blue 15, C.I. Direct Blue 67, C.I. Direct Blue 71, C.I. Direct Blue 98, C.I. Direct Blue 168, C.I. Direct Blue 202, C.I.. Direct Blue 236, C.I. Direct Blue 249, C.I. Direct Blue 270, C.I. Direct Green 59, C.I. Direct Green 85, C.I. Direct Brown 44, C.I. Direct Brown 106, C.I. Direct Brown 195, C.I. Direct Brown 210, C.I. Direct Brown 223, C.I. Direct Brown 224, C.I. Direct Black 1. C.I. Direct Black 17, C.I. Direct Black 19, C.I. Direct Black 54. Also preferred are JP-A-62-70802, JP-A-1-161202, JP-A-1-172906, JP-A-1-172907, JP-A-1-183602, JP-A-1-248105, Dichroic dyes described in JP-A-1-265205 and JP-A-7-261024. These dichroic dyes can be used in combination of two or more to obtain dichroic molecules with different hues. When a dichroic dye is used, an absorption thickness of 4 μm or more can be used in the present invention, as described in JP-A-14-082222.

Too little content of dichroic molecules in the film will result in a low degree of polarization, and too much content will reduce light transmittance. Therefore, the content of dichroic molecules is usually adjusted to be within a range of 0.01% by weight to 5% by weight relative to the polyvinyl alcohol polymer constituting the film matrix.

The thickness of the polarizing sheet is preferably 5 μm-40 μm, more preferably 10 μm-30 μm, especially preferably 10-22 μm. Even if the polarizing sheet is made very thin, i.e. 5-22 μm, the transmittance of the polarizing sheet at 700 nm on the crossed Nicols is 0.001%-0.3%, and the transmittance at 410 nm is also 0.001%-0.3 %. The upper limit of the light transmittance at 700 nm on crossed Nicols is preferably 0.3% or less, more preferably 0.2%. The upper limit of the light transmittance at 410 nm is preferably 0.3% or less, more preferably 0.08% or less, even more preferably 0.05% or less. Therefore, the light leakage defect (graphic frame defect) of the peripheral part of the graphic display device caused by the shrinkage of the polarizing sheet related to the temporary change can be improved, thereby obtaining a neutral gray color without a bluish color, thereby obtaining a preferred image Display quality.

It has been found that when the polarizing sheet is made very thin, i.e., 5-22 μm, by adding dichroic materials such as iodine and other dichroic dyes that show absorption under the corresponding wavelength range to the polarizing sheet as a hue adjuster, and in Adding a hardener such as boric acid together with a dichroic material such as iodine can effectively reduce the light transmittance in the wavelength range of 700nm and 410nm on the crossed Nicols. It is also effective to mix and add the above substances.

The above-mentioned tone adjusters may be used in combination of two or more. When the added coloring substances have absorption in the wavelength range of 410 nm or 700 nm, they will satisfy the object of the present invention. It is preferable that these coloring substances have a main absorption in the wavelength range of 380nm-500nm or 600nm-720nm. The content of these coloring substances can be determined arbitrarily according to the absorbance and dichroism ratio of the coloring substances used. There is no particular limitation in either case, as long as the light transmittance at 700 nm is 0.3% or less, and the light transmittance at 410 nm is 0.3% or less on crossed Nicols.

The above-mentioned color tone adjuster may be added to the polarizing sheet by any method including immersion, coating or spraying, among which immersion is preferred. The agent may be added before or after stretching, and is preferably added before stretching in consideration of improvement in polarization performance. This agent can be added alone, or in the dyeing process described later, or in the process of adding the hardener, or in both processes.

The thickness ratio of the polarizing sheet to the transparent protective film described later is preferably in the range of 0.01 ≤ A (thickness of the polarizing sheet)/B (thickness of the transparent protective film) ≤ 0.16, as described in JP-A-14-174727 .

The aforementioned transparent protective films are usually provided in roll form, and are preferably bonded together on a continuous substrate to correspond to axially long polarizing sheets. In this case, the orientation axis (slow phase axis) of the protective film may face any direction, and for easier handling, it is preferable that the orientation axis is parallel to the axial direction.

In addition, there is no particular limitation on the angle between the slow phase axis (orientation axis) of the protective film and the absorption axis (stretching axis) of the polarizing sheet, and the angle can be arbitrarily determined according to the use of the final polarizing plate. The long polarizers used in the present invention are not parallel to the axial absorption axis. Therefore, when the protective film parallel to the orientation axis of the axial direction is continuously adhered to the long polarizing plate, a polarizing plate is obtained in which the absorption axis of the polarizing sheet is not parallel to the orientation axis of the protective film. A polarizing plate adhered in such a way that the absorption axis of the polarizing sheet is not parallel to the orientation axis of the protective film is effective to obtain excellent dimensional stability. This feature is preferably exhibited when the polarizing plate is used only for a liquid crystal display device. Dimensional stability is particularly effectively exhibited when the inclination angle between the slow phase axis of the protective film and the absorption axis of the polarizing plate is between 10-90°, preferably between 20-70°.

[Swelling Control of Polymer Film of Polarizer and Method of Adding Dichroic Substance and Hardener]

The polarizing plate of the present invention can be produced by the following methods: swelling, dyeing, curing, stretching, drying, adhesion of a transparent protective film, and drying after adhesion. The sequence of the above-mentioned dyeing, curing and stretching processes can be changed arbitrarily or several processes can be combined and carried out simultaneously. The polarizing plate of the present invention can preferably be produced by specifically performing the above-mentioned swelling, dyeing and drying processes as follows.

(A) When the polymer film of the polarizing plate in the above swelling process is a PVA film, the film is soaked in water in advance to promote dyeing of a dichroic substance called iodine. In this case, the temperature is kept between 30-50°C, preferably between 35-45°C.

(B) In the dyeing process, the polymer film of the polarizer is dyed with iodine, a dichroic substance. In this case, boric acid (hardening agent) is added to iodine in a weight ratio ranging from 1 to 30 times.

(C) The stretched polarizing sheet is dried during the drying process. In this case, the temperature is kept at 80°C or lower, preferably 70°C or lower. The above process is explained later.

(A method of making the polarizing sheet thin)

The polarizing sheet can be made thinner by conventional stretching methods such as increasing the stretching ratio or using a thinner PVA film. A commonly used PVA film has a thickness of 75 µm, for example, "VF-P" or "VF-PS" produced by Kuraray Co., Ltd. In this case, when the polarizing sheet is stretched 8 times or more in the axial direction by perpendicular uniaxial stretching, the resulting film has a thickness of 20 µm or less. When the polarizing sheet is stretched 4 times or more by a horizontal uniaxial stretching process based on a tenter system, the resulting film has a thickness of 20 µm or less. Also, when the PVA film is made thin, or has a thickness of 50 µm or less and is stretched 6 times or more by a uniaxial stretching process, the resulting polarizing sheet has a thickness of 20 µm or less.

A stretching method can also be used in the present invention, wherein the polymer film of the polarizing sheet is uniaxially stretched in the transport direction, or after being uniaxially stretched, in addition to the above-mentioned uniaxial stretching process, the film is stretched in the transverse direction stretch. This method is commonly referred to as biaxial stretching. The process is usually carried out on the basis of a tenter frame system or by a simultaneous biaxial stretching method on the basis of a tubular process. In this method, a 75 µm thick PVA film is stretched 4 times or more in the axial direction and 1.5 times or more in the transverse direction to obtain a polarizing sheet having a thickness of 20 µm or less.

A stretching method preferably used in the present invention is a diagonal stretching method described in JP-A-2002-86554. In this method, a PVA film having a thickness of 125 μm or less is stretched 4 times or more to provide a polarizing sheet having a thickness of 20 μm or less.

In the present invention, a polarizing sheet having a thinner thickness is more preferable in view of defects related to light leakage (frame defects) and weight reduction of polarizing plate elements. However, an excessively thin film will cause problems such as film cutting during stretching, poor handling of the film soaked in a dyeing solution or curing solution, and cracking of the stretched film during drying.

Therefore, in the present invention, the thickness of the polarizing sheet is preferably 5 μm-22 μm, more preferably 8 μm-20 μm.

[Description of each process]

Hereinafter, each process for producing the polarizing plate of the present invention is explained.

(expansion process)

The expansion process is preferably carried out with water only. However, as described in JP-A-10-153709, the polarizing sheet material can be swelled by controlling the expansion degree of the polarizing sheet material using a boric acid solution so as to achieve stable optical characteristics and prevent the polarizing sheet material from wrinkling on the production line.

In addition, the expansion process may be performed at any temperature and time, preferably at a temperature of 10-50° C. for 5 seconds or longer. When no dichroic coloring substance is used, the aforementioned conditions are carried out at 30-50°C, preferably 35-45°C, for 5 seconds to 600 seconds, more preferably 15 seconds to 300 seconds.

(dyeing process)

The dyeing process can be performed as described in JP-A-2002-86554. In addition to soaking, the dyeing method can also be carried out by any method such as coating or spraying iodine or dye solution. There is no particular limitation on the dichroic substance used for dyeing, and in order to obtain a high-contrast polarizer, iodine is preferred. Preferably the dyeing process is carried out in the liquid phase.

When iodine is used, the dyeing process is performed by soaking the PVA film in an iodine-potassium iodide solution. Preferably, the content of iodine is 0.05-20g/L, the content of potassium iodide is 3-200g/L, and the weight ratio of iodine to potassium iodide is 1-2000. It is also preferred that the dyeing time is 10-1200 seconds and the solution temperature is 10-60°C. More preferably, the iodine content is 0.5-2g/L, the potassium iodide content is 30-120g/L, the weight ratio of iodine to potassium iodide is 30-120, the dyeing time is 30-600 seconds, and the solution temperature is 20-50°C.

As explained earlier, it is also effective to add a boron compound such as boric acid and borax as a hardening agent while performing the dyeing process and the curing process described later. When boric acid is used, it is preferable to add boric acid to iodine in a weight ratio of 1-30. Also, in this process, a dichroic coloring substance is also preferably added, preferably in an amount of 0.001-1 g/L. A constant addition in aqueous solution is important to maintain polarization properties. Production is therefore preferably carried out in a continuous manner with the addition of iodine, potassium iodide, boric acid and dichroic coloring substances. This addition can be done in solution or solid state. When adding the solution, a small amount of the solution to maintain a high concentration can be added as needed.

(curing process)

During curing, the crosslinker is preferably added by soaking or applying a solution of the crosslinker. The curing process can be carried out in separate steps as described in JP-A-11-52130.

Crosslinking agents include those compounds described in US Reissued Patent 232897 (reissued patent). As described in Japanese Patent No. 3357109, polyvalent aldehydes can be used as crosslinking agents to improve dimensional stability, and boric acid is most preferred.

When using boric acid as a crosslinking agent for the curing process, metal ions can be added to the boric acid/potassium iodide solution. Zinc chloride is preferred as the metal ion, but zinc salts such as zinc halide, zinc sulfate, and zinc acetate may be used instead of zinc chloride, as described in JP-A-2000-35512.

The curing process is preferably carried out by soaking the PVA film by adding zinc chloride to prepare a boric acid/potassium iodide solution. Preferably the content of boric acid is 1-100 g/L, the content of potassium iodide is 1-120 g/L, the content of zinc chloride is 0.01-10 g/L, the curing time is 10-1200 seconds and the solution temperature is 10-60°C. More preferably the content of boric acid is 10-80g/L, the content of potassium iodide is 5-100g/L, the content of zinc chloride is 0.02-8g/L, the curing time is 30-600 seconds and the solution temperature is 20-50°C . As previously explained, it is also effective to carry out the dyeing process by adding a dichroic coloring substance simultaneously with the process, the details of which have been described.

(stretching process)

As previously explained, the stretching is adjusted to obtain a polarizing sheet of 22 μm or less after stretching, followed by a uniaxial stretching method as described in US Patent No. 2,454,515. In the present invention, an oblique stretching method based on a tenter system as described in JP-A-2002-86554 is preferable.

Hereinafter, the oblique stretching method used in the present invention will be described.

Fig. 7 shows a typical example of a polymer film to be subjected to diagonal stretching in a rough plan view. The oblique stretching method used in the present invention includes the process of adding the unprocessed film shown in (a) along the direction shown by arrow (i), the process of stretching in the width direction shown in (b), And the process of adding the stretched film shown in (c) as a raw material to the next process, wherein the next process is in the direction shown in (ii). When the "stretching process" is mentioned later herein, the process includes all these processes of (a)-(c), and refers to the whole process of carrying out the oblique stretching method used in the present invention.

The film is fed continuously as raw material from direction (i) and first fixed at point B1 by the clamp on the left as viewed from the upstream side. At this time, the other end of the film was not fixed and no tension was obtained in the width direction. More specifically, point B1 is not a substantially fixed starting point (hereinafter referred to as a "substantially fixed starting point" hereinafter). The substantially fixed start point is defined as the point at which both ends of the film are fixed for the first time according to the method of the present invention. The substantially fixed start point is indicated by two points, namely, the fixed start point A1 on the further downstream side, and the point C1 where a line drawn approximately perpendicularly from A1 to the film on the joining surface 21 intersects the locus 23 of the clamp on the opposite side. When the grippers are moving at substantially similar speeds at both ends based on this point, A1 moves from A2, A3...An per unit time and C1 moves from C2, C3...Cn in a similar manner. More specifically, the line connecting the points An and Cn through which the elementary grippers pass at the same time provides the direction of stretching at said time.

In the oblique stretching method, as shown in Fig. 7, An moves slower than Cn and step by step to incline the stretching from the moving direction to the ground direction. The substantially fixed release point (hereinafter referred to as the "substantial fixed release point") is defined as two points, namely, the point Cx released from the more upstream clamp, and the center 22 of the film fed from Cx to the next process. The point Ay where the line drawn approximately perpendicular intersects the track 24 of the gripper on the opposite side. The distance W between the movement difference Ay-Ax (or |L1-L2|) between the right and left grippers passing through the end point of the basic stretching process (basic fixed release point) and the basic fixed release point (between Cx and Ay The ratio between the distance) determines the stretch angle of the finished film. In other words, the inclination angle θ formed between the stretching direction and the moving direction to the next process is an angle satisfying the following formula (III-a).

Formula (III-a): tanθ＝W/|L1-L2|

The end of the film shown at the upper end in FIG. 7 is fixed to 28 after point Ay, however, 28 is not a substantially fixed release point since the other end is not fixed and thus no widthwise stretch is obtained.

As explained above, in the oblique stretching method, the basic fixing start points at both ends of the film are not simple fixing points of the right and left grippers. For a more rigorous description, the two basic fixation start points are defined as the points where the line connecting the right or left fixation point to the other is approximately perpendicular to the centerline of the film added to the process of fixing the film, and are also defined as being located at The most upstream point. In a similar manner, in the present invention, the two basic fixed release points are the points where the line connecting the right or left fixed point with the other fixed point is approximately perpendicular to the center line of the film added to the next process, and is also defined as The two most downstream points. In this case, "substantially perpendicular" means that the centerline of the film is at 90 ± 0.5° to the line connecting the right or left substantially fixed start point or the right or left substantially fixed release point.

When using a stretching machine based on a tenter system to obtain the difference between the right and left movement processes, there is often a large gap between the fixed point of the clamp and the starting point of the basic fixed due to mechanical constraints such as the length of the track , and presents a situation with a large gap between the point of release from the clamp and the point of substantially fixed release. The object of the present invention will be satisfied when the movement process between the above-defined substantially fixed start point and substantially fixed release point satisfies the relationship of the following formula (III) and the difference in the moving speed of the clamp in the axial direction is less than 1%. The difference in movement speed is preferably less than 0.5%, most preferably less than 0.05%. In this case, the speed refers to the length of the trajectory that the right and left grippers move forward per minute. In ordinary stretching machines such as those based on a tenter system, the speed changes on a smaller than second time scale depending on the number of revolutions of the sprocket drive chain and the cycle of the drive motor, often resulting in a change in speed of several Percentage point change, which is not consistent with the speed difference described in the present invention.

Formula (III): |L2-L1|＞0.4W

Also, when stretching the polymer film of the polarizing sheet, it is preferable to stretch the polymer film while maintaining the volatile matter content ratio at 5% by volume, and then reduce the content ratio while shrinking the film. This treatment prevents the film from wrinkling or twisting. The volatile content ratio used in the present invention refers to the volume of volatile compounds contained in a unit volume of film, and is a value obtained by dividing the volume of volatile compounds by the volume of the film.

Methods of adding volatile compounds include:

(1) Casting the volatile compound onto the film to add solvent and water,

(2) Soaking the volatile compound in a solvent and water and coating and spraying the resultant before stretching, or

(3) During the stretching process, solvent and water are applied.

Since a hydrophilic polymer film such as polyvinyl alcohol contains water in a hot-humid atmosphere, moisture control and subsequent stretching are performed in a hot-humid atmosphere or stretching is performed in a hot-humid atmosphere, thereby adding volatile compounds. Besides these methods, any other methods may be used for this purpose as long as they can keep the volatile compounds of the polymer film at 5% by volume or more.

The preferred volatile content ratio varies with the type of polymer film. The proportion of volatiles content can be increased to the highest possible extent, as long as the polymer film can be loaded. The volatile content ratio of polyvinyl alcohol is preferably 10-100% by volume. Cellulose acylate is preferably 10-200% by volume.

(drying process)

Drying conditions were controlled in accordance with the method described in JP-A-2002-86554. As explained above, the drying process is performed at a temperature of 80°C or lower, preferably 70°C or lower. The preferred drying time is 30 seconds to 60 minutes.

(The process of attaching the transparent protective film)

The polarizing sheet of the present invention is provided as a polarizing plate with transparent protective films adhered to both sides. The two transparent protective films can be the same or different. This attachment is preferably performed by first supplying an adhesive solution and then adhering the transparent protective film to the polarizing sheet using a pair of rollers. The thickness of the binder solution layer after drying is preferably 0.001-5 μm, more preferably 0.005-3 μm.

Also, in order to remove recording groove-like unevenness caused by stretching the polarizing sheet, it is preferable to adjust the moisture content of the polarizing sheet at the time of adhesion as described in JP-A-2001-296426 and JP-A-2002-86554. In the present invention, it is preferable to maintain a moisture content of 0.1 to 30% by weight.

There is no particular limitation on the adhesive used to bond the polarizing sheet to the transparent protective film. Preferred binders are PVA resins (including modified PVA into which acetoacetyl groups, sulfonic acid groups, carboxyl groups, oxyalkylene groups, and other groups have been introduced) and boron compound solutions. PVA resin is more preferred.

(drying process after adhesion)

The drying process after the adhesion is performed under the conditions described in JP-A-2002-86554, and preferably at a temperature of 30°C to 100°C for 30 seconds to 60 minutes.

The polarizing plate prepared by the above process preferably contains the following elements in the polarizing sheet, namely, iodine 0.1-3.0 g/m ² , boron 0.1-5.0 g/m ² , potassium 0.1-2.0 g/m ² and zinc 0.001-2.0 g /m ² . It is particularly preferred that the light transmittance be maintained at 42.5% or greater, for which reason the iodine content is preferably low. The preferred iodine content is 0.1-1.0 g/m ² .

Moreover, in order to improve the dimensional stability of the polarizer, an organic titanium compound and/or an organic zirconium compound may be added during any of the dyeing, stretching or curing processes, thereby adding at least one selected from the organic titanium compound and the organic zirconium compound. A compound, as described in Japanese Patent No. 3323255.

[Characteristics of Polarizer]

(transmittance and degree of polarization)

The polarizer of the present invention preferably has a light transmittance of 42.5%-49.5%, more preferably 42.8%-49.0%. Moreover, the polarizer preferably has a parallel light transmittance of 36%-42%, and a cross light transmittance of 0.001%-0.05%. The light transmittance of the above type is defined by the following formula (VII) based on JIS Z-8701.

T＝K∫S(λ)y(λ)τ(λ)dλ

In this case, K, S(λ), y(λ), and τ(λ) represent the following meanings

$\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 100</span>}}{<span\; class="notranslate">\; \&Integral;</span>\mathrm{<span\; class="notranslate">\; S</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&lambda;</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&lambda;</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; d\&lambda;</span>}}$

S(λ): Spectral distribution of standard light used to indicate color

y(λ): color matching function of XYZ system

τ(λ): Spectral transmittance

λ: measured wavelength [nm]

The degree of polarization of the polarizing plate of the present invention is preferably 99.900% to 99.999%, more preferably 99.940% to 99.995%, which is defined by the following formula (VIII).

In addition, the dichroic ratio (Rd) defined by the following numerical formula (IX) is preferably 48-1215, more preferably 53-525.

Considering the parallel light transmittance in the wavelength range of 440-670 nm in the polarizing plate of the present invention, the difference ΔT between the maximum value (Tmax) and the minimum value (Tmin) of the parallel light transmittance T is 6% or more Small, preferably 4% or less, more preferably 2% or less. Also, the transmittance ratio R _T1 (parallel transmittance at 490nm/parallel transmittance at 550nm) and transmittance ratio R _T2 (parallel transmittance at 610nm/parallel transmittance at 550nm) showing light transmission characteristics Light transmittance) are all in the range of 1.00±0.02, preferably in the range of 1±0.01. These characteristics are preferred in reflective and transflective liquid crystal display devices.

Considering the optical properties of polarizers arranged on crossed Nicols, the ratio of the absorption peak (Ap ₁ ) in the wavelength range of 550-650nm to the absorption peak (Ap ₂ ) in the wavelength range of 450-520nm is preferably is 1.5 or less, more preferably 1.4 or less, and especially preferably 1.2 or less. It is preferable in the present invention that black display is enhanced by reducing light leakage due to the arrangement of polarizers on crossed Nicols, or that a neutral tone can be obtained.

Also preferred are the parallel transmittance Tp ₄₄₀ and the cross transmittance Tc ₄₄₀ in the wavelength range of 440 nm, the parallel transmittance Tp ₅₅₀ and the cross transmittance Tc ₅₅₀ at 550 nm and the parallel transmittance Tp at 610 nm ₆₁₀ and the cross transmittance Tc ₆₁₀ simultaneously satisfy the following formulas (X)-(XIII).

(X): 0.85≤Tp ₄₄₀ /Tp ₅₅₀ ≤1.10

(XI): 0.90≤Tp ₆₁₀ /Tp ₅₅₀ ≤1.10

(XII): 1.0≤Tc ₄₄₀ /Tc ₅₅₀ ≤8.0

(XIII): 0.08≤Tc ₆₁₀ /Tc ₅₅₀ ≤1.10

By keeping the light transmittance in the above range to provide reflective and translucent reflective liquid crystal display devices with excellent display images and no difficulty in clearly reproducing colors, backlight (at 440nm, 550nm and 610nm At three wavelengths) the spectral line bee and the change in cross transmittance decrease.

It is also preferable to adjust the standard deviation of the parallel light transmittance every 10 nm at a wavelength of 420-700 nm to 3 or less, and to adjust the standard deviation of every 10 nm (parallel light transmittance/cross transmittance) in the wavelength range of 420-700 nm to 3 or less. light rate) to 300 or greater. This adjustment can realize a display image with good contrast in the liquid crystal display device, thereby effectively making the color display neutral on a white image display.

(tone)

The hue presented on the polarizing plate of the present invention is preferably evaluated by lightness index L* and chromaticity indices a ^* and b ^* in ^the L ^* a ^* b ^* display color system recommended as the CIE equivalent perception space. L ^* , a ^* and b ^* are defined by formula (XIV) using X, Y and Z.

${\mathrm{<span\; class="notranslate">\; L</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 116</span>}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>}^{\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 16</span>}$

${\mathrm{<span\; class="notranslate">\; a</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 500</span>}<span\; class="notranslate">\; [</span>{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>}^{\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}}<span\; class="notranslate">\; -</span>{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>}^{\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}}<span\; class="notranslate">\; ]</span>$

${\mathrm{<span\; class="notranslate">\; b</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 200</span>}<span\; class="notranslate">\; [</span>{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>}^{\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}}<span\; class="notranslate">\; -</span>{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Z</span>}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; Z</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>}^{\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}}<span\; class="notranslate">\; ]</span>$

In this case, X _o , Y _o and Z _o represent the three excitation values of the light source. In the case of standard light C, X _o =98.072, Y _o =100, Z _o =118.225, and in the case of standard light D ₆₅ , X _o =95.045, Y _o =100, Z _o =108.892.

In a single polarizer, a ^* is preferably in the range of -2.5 to 0.2, more preferably -2.0 to 0, and b ^* is preferably in the range of 1.5-5, more preferably 2-4.5. In both polarizers, a ^* of parallel transmitted light is preferably in the range of -4.0 to 0, more preferably -3.5 to -0.5. In both polarizers, b ^* of parallel transmitted light is preferably in the range of 2.0-8, more preferably 2.5-7. In both polarizers, a ^* of the cross transmitted light is preferably in the range of -0.5 to 2, more preferably 0-1.0. In both polarizers, b ^* of cross transmitted light is preferably in the range of -2.0 to 2, more preferably -1.5 to 0.5.

Hue can be evaluated by X, Y and Z calculated chromaticity coordinates (x, y). Among the two polarizers, it is preferable that the chromaticity (x _p and y _p ) of the parallel transmitted light and the chromaticity (x _c and y _c ) of the crossed transmitted light can be adjusted to, for example, JP-A-14-214436, JP-A-14-214436, JP - Within the range described in A-13-166136 and JP-A-14-169024, or the relationship between hue and absorbance can be adjusted to within the range described in JP-A-13-311827.

(view angle characteristics)

When the polarizers are arranged in the crossed Nicols state and light is irradiated at a wavelength of 550 nm, the light transmittance between radiation perpendicular to the light and radiation at an angle of incidence of 40° to the normal to the direction of 45° relative to the polarization axis The ratio and xy chromaticity difference are adjusted to the ranges described in JP-A-13-166135 and JP-A-13-166137. The vertical transmittance (T ₀ ) of polarizer laminates arranged in crossed Nicols state, and the transmittance in the direction 60° to the normal of the laminate (T ₆₀ ) and vertical transmittance The rate ratio (T ₆₀ /T ₀ ) is preferably adjusted to 10000 or less as described in JP-A-10-068817. When natural light is irradiated at any given angle up to an elevation angle of 80° to the normal of the polarizer, the difference in transmittance between transmitted light at a wavelength range of 20nm or less within the transmission spectrum range of 520-640nm The value is preferably adjusted to 6% or less as described in JP-A-14-139625. Also, the difference in luminance of transmitted light at arbitrary positions separated by 1 cm on the film is also preferably adjusted to 30% or less, as described in JP-A-08-248201.

(orientation)

In general, higher orientation of PVA can provide better polarization performance. The orientation is preferably in the range 0.2-1.0 in terms of order parameter values calculated by different means such as polarized Raman scattering or polarized FT-IR. Also preferably, as described in JP-A-59-133509, the difference between the orientation coefficient of the polymer segment in the amorphous region of the polarizing plate and the orientation coefficient of the occupant molecules (0.75 or more) is adjusted to at least 0.15; as As described in JP-A-04-204907, the orientation coefficient of the amorphous region of the polarizer is adjusted to 0.65-0.85 in terms of order parameter value, or the orientation coefficient of higher iodide ions such as I ₃ ^- and I ₅ ^- is adjusted to 0.8-1.0.

<Polarizer with anti-reflection function>

The polarizer of the present invention is a polarizer having an antireflection function prepared by coating the above-mentioned antireflection film on the other side of the transparent protective film of the polarizer made of the above-mentioned polarizer and transparent protective film.

The polarizing plate with antireflection film was produced by the following methods (1)-(3).

(1) The face of the transparent protective film laminated with the antireflective film opposite to the antireflective film is adhered to the face of the polarizing sheet of the polarizing plate formed by adhering the transparent protective film and the polarizing sheet using an adhesive

(2) The surface of the transparent protective film laminated with the antireflection film is made hydrophilic by saponification or otherwise on the surface opposite to the antireflection film, and then the polarizing sheet is adhered to the film thus treated using an adhesive on the surface

(3) Coating an antireflection film on the transparent protective film of the polarizing plate formed by adhering the transparent protective film to the polarizing sheet.

The method (2) or (3) is a preferred embodiment since the polarizing plate can be made thinner. Also, it is preferable in the method (2) to continuously adhere the transparent protective film on which the antireflection film is coated.

[Characteristics of polarizers with anti-reflection function]

[Optical properties and weather resistance]

(reflectance ratio)

The average value (that is, the average reflectance ratio) of the specular reflectance in the wavelength range of 450nm-650nm at an incident angle of the polarizer with antireflection function of the present invention is preferably 2.5% or less, more preferably 1.8% or less, even more preferably 1.4% or less.

The above specular reflectance at an angle of incidence of 5° is the ratio of the light intensity of light reflected by the sample at -5° from the normal direction to light incident at +5° from the normal to indicate the reflection from the specular reflection on the back side the extent of the image. When used as an antireflection film having an antiglare function, light reflected at an angle of -5° in the normal direction is weakened by scattered light to some extent resulting from surface unevenness imparting an antiglare function. Therefore, the specular reflectance can be used to determine the contribution reflecting the anti-glare function and the anti-reflection function.

In the polarizing plate with anti-reflection function, the average value of the specular reflectance at an incident angle of 5° in the wavelength range of 450nm-650nm is 2.5% or less, and the reflection image on the back has no involvement or defect, such as in the display Application of the film on the surface of the device found no reduction in visibility. Therefore, the polarizing plate can be preferably used in the present invention.

In addition, when the antireflection film of the present invention is laminated with a multilayer antireflection film, the average value of the specular reflectance (that is, the average reflectance ratio) at an incident angle of 5° in the wavelength range of 450nm-650nm is 0.5 % or less, preferably 0.4% or less, more preferably 0.3% or less, thereby preventing a significant decrease in visibility due to reflection of external light on the surface of the display device.

In the wavelength range of 380-680 nm, the change in the average reflectance ratio of the polarizing plate of the present invention before and after the photostability test is preferably 0.4% or less, more preferably 0.2% or less. When the ratio is within the above range, no practical problem arises.

(color and in-plane rate of change)

It is preferable that the polarizing plate having an anti-reflection function has the color of the specularly reflected light obtained from the 5° incident light of the CIE standard illuminant D ₆₅ at a wavelength of 380nm-780nm, that is, L ^* in the color space of CIE1976L ^* a ^* b ^* , a ^* and b ^* values are respectively in the following ranges: 3≤L ^* ≤20, 0≤a ^* ≤7 and -10≤b ^* ≤0. When these values are within the above ranges, the color of reflected light from magenta to bluish violet is reduced, which has been an unsolved problem with conventional polarizers. Also, when these values are in the ranges of 3≤L ^* ≤10, 0≤a ^* ≤5, and -7≤b ^* ≤0, the color of reflected light is significantly lowered and the color of external light of bright light such as indoor fluorescent lamps is slightly reflected It is neutral and does not relate to the application of polarizers on liquid crystal display devices. More specifically, the range of a ^* ≤ 7 does not make the red color too strong, and the range of a ^* ≥ 0 does not make the cyan color too strong, so they are preferable. In addition, the range of b ^* ≥ -10 does not make the blue color too strong, and the range of b ^* ≤ 0 does not make the yellow color too strong, so both are preferable.

In the present invention, it is preferable that the above-mentioned respective values of L ^* , a ^* and b ^* are constant over the entire surface of the displayed image. Also, the in-plane variation rate of each value is preferably 20% or less, more preferably 8% or less. When the above values and rate of change are within these ranges, a displayed image with no change in color and excellent visibility is provided.

Specular reflectance and color were measured with a spectrophotometer V-550 (manufactured by JASCO Corporation) equipped with an adapter ARV-474. Specifically, the specular reflectance was measured at an incident angle of 5° and an output angle of 5°C in the wavelength range of 380-780 nm, and the average reflectance ratio in the wavelength range of 450-650 nm was calculated to evaluate antireflection performance. Also, the L ^* value, a* value, and b of the CIE 1976L ^* a ^* b ^* color space representing the color of the specularly reflected light ^of 5° incident light from the CIE standard illuminant D ₆₅ were calculated using the reflectance spectrum thus determined ^* value, from which the color of reflected light can be evaluated.

The color change of the reflected light can be greatly reduced by properly adjusting the components constituting the polarizer of the present invention through the following treatment, that is, the color of the transparent protective film itself and the color change are kept within the above-mentioned range, providing unevenness on the homogenized surface configuration in which the unevenness of the film thickness is reduced, thereby forming an anti-reflection film and making the color of the polarizing sheet more neutral.

In addition, the color uniformity of reflected light is measured with reference to the reflectance spectrum of reflected light at 380-680 nm. The average values of a ^* and b ^* are respectively determined on the L ^* a ^* b ^* chromaticity diagram, and the difference (ΔA) between the maximum value and the minimum value of each of the a ^* value and b ^* value is divided by the average value and multiplied by 100 Get the color change rate. The rate of change is preferably 30% or less, more preferably 20% or less, most preferably 8% or less.

The color change ΔE of the polarizing plate with antireflection function of the present invention before and after the weathering test is preferably 15 or less, more preferably 10 or less, most preferably 5 or less.

When the value is within the above range, low reflection can be obtained while reducing the color of reflected light. Therefore, the color of ambient light that slightly reflects bright light such as indoor fluorescent lamps is made neutral, thereby preferably improving the quality of displayed images when used, for example, on the outermost surface of a graphic display device.

The polarizing plate having an antireflection function of the present invention is characterized in that the optical characteristics and mechanical properties (tear strength, scratch strength and tackiness) of the antireflection film are maintained to such an extent that no problem occurs after a weathering test. Specifically, the polarizing plate also has such a feature that the change in the above-mentioned characteristics after the weathering test is maintained at such a level that no problem arises.

The weather resistance test of the present invention refers to using a sunlight weather resistance test box ["S-80", manufactured by Suga Test Instruments Co., Ltd.], at 50% RH and 150 hours according to JIS K-5600-7-7: 1999 The experiments were carried out under the treatment time.

(Durability of light transmittance and degree of polarization dependent on temperature and/or humidity)

The polarizing plate with anti-reflection function of the present invention is preferably 3% or more in terms of absolute value, before and after the polarizing plate is left to stand in an atmosphere of 60° C. and 90% RH for 500 hours. smaller. Furthermore, the rate of change in light transmittance of the polarizing plate is particularly preferably 2% or less, and the rate of change in polarization degree is 1.0% or less, preferably 0.1% or less, in absolute value. These conditions can be achieved by a stretched film of a hydrophilic polymer containing more than 0.6% by weight of a dichroic substance and a polarizing sheet made of a cellulose acylate film excellent in moisture resistance and preferably usable in the present invention. As described in JP-A-07-077608, the degree of polarization of the polarizing plate after standing at 80° C. and 90% RH for 500 hours is preferably 95% or more. Also, the light transmittance of the polarizing plate is preferably 38% or more.

Further, the rate of change in light transmittance and polarization degree of the polarizing plate is preferably 3% or less in absolute value before and after the polarizing plate is left standing in a dry atmosphere at 80°C for 500 hours. Furthermore, the rate of change in light transmittance of the polarizing plate is particularly preferably 2% or less, and the rate of change in polarization degree is 1.0% or less, preferably 0.1% or less, in absolute value.

[Dimensional change rate]

When standing in a heated atmosphere at 70° C. for 120 hours, the dimensional change rate of the antireflection polarizer of the present invention in the direction of the absorption axis and the dimensional change rate in the direction of the polarization axis are preferably within ±0.6%.

Considering the dimensional properties when the polarizer is heated, since the change of the polarizer in the direction of the absorption axis and the direction of the polarization axis is less anisotropic, the shrinkage of the polarizer makes the load applied to the in-plane of the plastic unit uniform, thereby Solve the bending of irregularly shaped panels, which has been a problem in the assembly of liquid crystal display devices. It is more preferable that the dimensional change rate D _A of the polarizing plate in the direction of the absorption axis and the dimensional change rate D _B in the direction of the polarization axis satisfy the following relationship.

-0.05＜(Dimensional change rate D _A -Dimensional change rate D _B )＜+0.05

By controlling the stretching process of the polarizing sheet, and adjusting the moisture content of the polarizing sheet when it is adhered to the transparent protective film (based on the total weight of the polarizing sheet, the moisture content of the polarizing sheet is usually less than 20% by weight, preferably 13-17% by weight , although it depends on the thickness of the polarizing sheet) can satisfy this relationship.

[other resistance]

As described in JP-A-06-167611, the shrinkage percentage of the polarizing plate when left to stand at 80° C. for 2 hours is preferably 0.5% or less. It is also preferable to adjust the change in spectral intensity ratio at 105 cm ⁻¹ and 157 cm ⁻¹ by Raman spectroscopy after the polarizer is left to stand in an atmosphere of 80° C. and 90% RH for 200 hours to JP-A-08-094834 and within the range described in JP-A-09-197127.

<Other functional layers>

The polarizing plate with antireflection function of the present invention is preferably used as a composite polarizing plate having functional layers such as viewing angle widening films for LCDs, antireflection films for reflective LCDs, and others. λ/4 plate on the opposite side of the transparent protective film of the transparent protective film.

[Optical Compensation Film]

It is preferable that the polarizing plate on the viewing side of the present invention is provided with an optical compensation film on the face opposite to the polarizing plate with the antireflection film. This structure can widen the viewing angle of images displayed on the liquid crystal display device. By laminating an optical compensation film on the transparent protective film opposite to the polarizer of the fixed antireflection film, by giving the transparent protective film itself the function of an optical compensation film, or by coating a layer with an optical compensation function on the transparent protective film, Optical compensation function can be given.

The optical compensation film includes a birefringent film in which a polymer film is subjected to a uniaxial or biaxial stretching process and a liquid crystal alignment film having an optically anisotropic layer made of a liquid crystal material showing birefringence on a transparent film. There is no particular limitation on the thickness of the optical compensation film, and the thickness is usually 5-100 μm. Among these optical compensation films, a liquid crystal alignment film having an optically anisotropic layer on a transparent film is preferable.

Raw materials of the polymer film constituting the birefringent film include, for example, polyvinyl alcohol, polyvinyl butyral, polymethyl vinyl ether, polyhydroxyethyl acrylate, hydroxyethyl cellulose, hydroxypropyl cellulose, Methylcellulose, polycarbonate, polyacylate, polysulfone, polyethylene terephthalate, polyethylene naphthalate, polyethersulfone, polyphenylene sulfide, polyphenylene ether, polypropylene Sulfone, polymethyl methacrylate, polyamide, polyimide, polyolefin, polyvinyl chloride, cellulose polymer, norbornene resin or their binary and terpolymers, graft copolymers and mixture. These polymer raw materials are oriented products (stretched films) subjected to stretching or the like.

[LC Alignment Film]

The preceding optically anisotropic layer is preferably designed to compensate the liquid crystal compound molecules in the liquid crystal cell at the time of black display of the liquid crystal display device. The orientation state of the liquid crystal compound molecules in the liquid crystal cell at the time of black indication varies depending on the mode of the liquid crystal display device. The orientation state of liquid crystal compound molecules in a liquid crystal cell has been described in IDW'00FMC7-2, pages 411-414.

(liquid crystal compound)

The liquid crystal compound used in the optically anisotropic layer may be rod-shaped or discotic liquid crystals, including polymer liquid crystals, low molecular weight liquid crystals, and even cross-linked low molecular weight liquid crystals that no longer exhibit any liquid crystal properties. Discotic liquid crystals are most preferred.

Preferred rod-shaped liquid crystals are those compounds described in JP-A-2000-304932.

Discotic liquid crystals include benzene derivatives described in the research report of C. Destrades et al. and Mol. Cryst., Vol. 71, p. 111 (1981), the research report of C. Destrades et al., Mol. Cryst., vol. , 141 pages (1985) and Physics lett., A, vol. 78, truxenon derivatives described in 82 pages (1990), research report of B. Kohne et al., Angew.Chem., 96 volumes, Cyclohexane derivatives described on p. 70 (1984); J.M. Lehn et al., J. Chem. Commun., p. 1794 (1985), J. Zhang et al., J.Am .Chem.Soc., Vol. 116, p. 2655 (1994) for azacridine and phenylacetylene macrocycles.

In general, the above-mentioned discotic liquid crystal is structured so that its molecular center has a mother nucleus, and linear alkyl groups, alkoxy groups, substituted benzoyloxy groups, etc. are radially substituted as linear groups, exhibiting liquid crystallinity. Discotic liquid crystals may not be limited to the above if the molecule itself has a negative uniaxial orientation and can impart a certain orientation. Moreover, the term "formed from discotic compounds" in the present invention means that the final products are not necessarily the above-mentioned compounds, but they include, for example, low-molecular discotic liquid crystals having groups that react under the action of light, heat, etc., and as a result, these groups The group undergoes polymerization or crosslinking under the action of light, heat, etc. to obtain a polymer and lose its liquid crystallinity. Preferred examples of the above discotic liquid crystals are those described in JP-A-8-50206.

Generally, the above-mentioned optically anisotropic layer is obtained by coating a solution of a discotic compound and other compounds (for example, plasticizers, surfactants, and polymers) dissolved in a solvent on an oriented film, drying the resultant, It is prepared by heating to the temperature at which the discotic nematic phase is formed, then cooling, and maintaining the orientation state (discotic nematic phase). Alternatively, by coating an alignment film with a solution of a discotic compound and other compounds (in addition, for example, a polymerization monomer photopolymerization initiator) dissolved in a solvent, drying the resultant, heating to a temperature at which a discotic nematic phase is formed, Polymerization (exposure to ultraviolet light, etc.) and cooling produces an optically anisotropic layer.

The thickness of the optically anisotropic layer is preferably 0.1-10 μm, more preferably 0.5-5 μm, most preferably 0.7-5 μm. However, in order to obtain higher optical anisotropy, this layer can be thicker (3 or 10 μm) depending on the mode of the liquid crystal cell.

The optical compensation layer includes well-known layers, and those having an optically anisotropic layer made of a compound with a discotic structural unit are preferable in view of widening the viewing angle, and the angle formed between the discotic compound and the transparent support Varies with the distance from the transparent support as described in JP-A-2001-100042.

The angle preferably increases with increasing distance from the plane of the transparent support on the optically anisotropic layer.

When the optical compensation layer is used as the protective film of the polarizing plate, it is preferable that the surface to be attached to the polarizing plate is subjected to saponification treatment, which is carried out in accordance with the aforementioned procedure.

Also preferred is an embodiment in which the optically anisotropic layer further contains cellulose ester, wherein an alignment layer is provided between the optically anisotropic layer and the transparent support, and the transparent support having the optical compensation layer of the optically anisotropic layer is placed between The normal direction of the transparent support plane has an optically negative uniaxial orientation and beam axis, and also satisfies the conditions of the numerical formula below.

      20＜{(nx+ny)/2-nz}×d＜400

In the above numerical formula, nx represents the in-plane refractive index of the layer in the direction of the slow phase axis (direction of maximum refractive index); In-plane refractive index; nz represents the refractive index in the thickness direction; d represents the thickness of the optical compensation layer.

(Oriented film)

An alignment film is generally used due to its function of controlling the alignment direction of liquid crystal compound molecules. A liquid crystal compound whose alignment state is fixed after alignment can also function as an alignment film. Therefore, an oriented film is not always an essential element in the present invention. For example, only an optically anisotropic layer on an orientation film, wherein the orientation state thereof is fixed, can be transferred onto a transparent protective film of a polarizing sheet, thereby providing the polarizing plate of the present invention.

Oriented films can be prepared by subjecting organic compounds (preferably polymers) to rubbing, subjecting inorganic compounds to batch evaporation, forming layers with microscopic groups, or agglomerating organic compounds (e.g., omega-tricosanoic acid, dioctadecylmethylammonium chloride and methyl stearate). It is also known that an alignment film having an alignment function is produced by applying a magnetic field or light irradiation.

The alignment film is preferably formed by subjecting a polymer to rubbing treatment. The polymer used to form the alignment film follows the principle that the molecular structure of liquid crystal molecules can be aligned.

In the present invention, it is preferable to bond a side chain with a cross-linking functional group (for example, a double bond) to the main chain, or to add a cross-linking functional group with a function of aligning liquid crystal molecules to the side chain to increase the alignment of liquid crystal molecules. Function.

A polymer capable of being cross-linked by itself or a polymer cross-linked by a cross-linking agent is a polymer that can be used as an oriented film. These polymers may also be used in combination of two or more.

Examples of polymers useful as oriented films include methacrylate copolymers, styrene copolymers, polyolefins, polyvinyl alcohol and modified polyvinyl alcohols, poly(N-methylolacrylamide), polyesters, Polyimide, vinyl acetate copolymer, carboxymethylcellulose and polycarbonate as described in paragraph [0022] of JP-A-8-338913. Most preferred are polyvinyl alcohols and modified polyvinyl alcohols. Aligned film-forming compounds such as modified polyvinyl alcohol compounds and crosslinking agents are, for example, those described in JP-A-2000-155216 and JP-A-2002-62426.

Oriented films can generally be formed by coating the above-mentioned polymer (material for forming an oriented film) on a support, followed by heating, drying (crosslinking) and rubbing. Crosslinking can be performed at any time after coating onto the support, as previously explained.

The oriented film can preferably be applied by spin coating, dip coating, curtain coating, extrusion coating, bar coating or roll coating methods. The bar coating method is particularly preferred.

The alignment film is directly formed on the transparent protective film (support), or formed after providing an undercoat layer on the transparent protective film. When forming an oriented film directly on a support, the film is made hydrophilic on its surface. It is preferable to use a transparent protective film of a polarizing plate as a support.

The inner coat can be formed by coating only the inner coat or a single layer of a resin such as gelatin containing both hydrophobic functional groups and hydrophilic groups (single layer method) as described in JP-A-7-333433, or as described in JP-A-7-333433 Described in JP-A-11-248940 by providing a layer that is sufficiently adhered to the polymer film as the first layer (hereinafter referred to as the first undercoat layer in the present specification), on which coating is sufficiently adhered to the oriented film. A combined hydrophilic resin layer such as gelatin is used as the second layer (referred to as the second inner coating hereinafter in the specification) (double-layer method).

As explained above, the oriented film is obtained by subjecting the surface of the polymer to rubbing treatment after crosslinking. Then, the alignment film is operated to align the liquid crystal molecules of the optically anisotropic layer provided on the alignment film. Thereafter, the alignment film polymer is reacted with the polyfunctional monomer contained in the optically anisotropic layer, or crosslinked with the alignment film polymer using a crosslinking agent as necessary.

The thickness of the oriented film is preferably in the range of 0.1-01 μm.

[Support on which optically anisotropic layer made of liquid crystal compound is coated]

The support on which the optically anisotropic layer is coated is not particularly limited as long as it is a plastic film with high light transmittance. Cellulose acylate which is a transparent protective film of a polarizing plate is preferable. Specifically, it is preferable to directly form an orientation film (not an essential film, as described above) and an optically anisotropic layer directly on the transparent protective film of the polarizing plate.

Since the support itself on which the optically anisotropic layer is coated plays an optically important role, it is preferable to adjust the Re retardation value of the support to 0-200 nm and the Rth retardation value to 0-400 nm.

It is preferable that the cellulose acylate film of the support has an ultraviolet-absorbing compound as the retardation adjusting agent, wherein the wavelength (λmax) of maximum absorption imparted to the ultraviolet-ray absorption spectrum of the solution is within a wavelength shorter than 400 nm. These compounds include UV absorbing compounds such as phenylsalicylic acid, 2-hydroxybenzophenone, benzotriazole and triphenyl phosphate. Aromatic compounds having at least two aromatic rings (those described in JP-A-2000-111914), benzo[9,10]phenanthrene compounds (those described in JP-A-2000-275434), rod-shaped Compounds (those described in JP-A-2002-363343, JP-A-2003-35821), discotic compounds (compounds having a 1,3,5-triazine skeleton and a porphyrin skeleton in the molecule (JP-A - those described in 2001-166144)). These compounds preferably have no substantial absorption in the visible region.

The birefringence index (Δn:nx-ny) of the support film is preferably 0 or 0.002. Also, the birefringence index {(nx+ny)/2-nz} of the film in the thickness direction is preferably 0 or 0.04.

The delay value (Re) is calculated according to formula (XV):

    Delay value (Re)＝(nx-ny)×d

where nx represents the in-plane refractive index of the retardation plate in the direction of the slow phase axis (in-plane maximum refractive index), and ny represents the in-plane refractive index of the retardation plate in the direction perpendicular to the slow phase axis.

The delay value (Rth) is calculated according to formula (XVI):

    Delay value (Rth)＝{(nx+ny)/2-nz}×d

Among them, nx represents the refractive index in the direction of the slow phase axis (the direction where the refractive index is maximized) in the film plane; ny represents the refractive index in the direction where the film advances toward the axis (the direction where the refractive index is minimized); nz represents the refractive index in the direction of the film thickness rate, and d represents the film thickness in nm.

The thickness of the cellulose acylate film used as an optical compensation film is preferably 20 to 200 μm, more preferably 30 to 120 μm.

When an optical compensation film is used as the protective film of the polarizing sheet, that is, when the film is attached to the polarizing sheet after the optically anisotropic layer is provided on the transparent protective film, the surface to be attached to the polarizing sheet is preferably according to The saponification was carried out in the steps described previously.

The polarizer on the viewing side is a laminated film consisting of antireflection film/transparent protective film/polarizing sheet/transparent protective film, or is made of antireflective film/transparent protective film/polarizing sheet/optical compensation film (transparent protective film/ (orientation film)/optical anisotropic layer) composition of the laminated film, thereby making the polarizer thinner and lighter and reducing costs. The antireflection film is also used as an upper transparent protective film of a polarizer, and the support on which an optically anisotropic layer is coated is also used as a lower transparent protective film, thereby providing physical strength, weather resistance, and antireflection function. A thinner and lighter polarizer with excellent visibility.

In this case, the polarizing plate and the optical compensation film are the same as those described for the viewing side polarizing plate (upper polarizing plate).

<Image display device>

The image display device of the present invention comprises the polarizing plate having anti-reflection function of the present invention arranged on the image display surface. Therefore, the polarizing plate having an antireflection function of the present invention can be used in image display devices such as liquid crystal display devices (LCD) and organic EL displays. The image display device of the present invention is preferably applicable to transmissive, reflective and semi-transmissive liquid crystal display devices based on any mode of TN, STN, IPS, VA and OCB. Further explanation below:

The liquid crystal display device may include any known conventional display device. They are, for example, "Comprehensive technology of reflective-type color LCD," Uchida, T., [CMC, 1999], "New development of flat panel displays," [ResearchDepartment, Toray Research Center Inc., 1996], "Present status and prospect of liquid crystal-related market" (lower and upper columns) [Fuji Chimera Research Institute, Inc., 2003] etc. display devices.

Specifically, they are preferably available for transmission based on modes of twisted nematic (TN), super twisted nematic (STN), vertically aligned (VA), in-plane switching (IPS) and optically compensated bend cells (OCB) type, reflective and semi-transmissive liquid crystal display devices.

And, because when the polarizing plate of the present invention is installed on display image size and is 17 inches or larger liquid crystal display device, can provide suitable contrast ratio and wide viewing angle and prevent the reflection of color tone change and external light, therefore preferred The polarizer.

[LCD based on TN mode]

Liquid crystal cells based on the TN mode are most commonly used as color TFT liquid crystal display devices and are described in a considerable amount of literature. The orientation of the liquid crystal cell based on the TN mode at the time of black display is the case where the rod-shaped liquid crystal molecules are raised in the center of the cell and placed near the cell substrate.

[LCD based on OCB mode]

The OCB mode-based liquid crystal cell is a bend alignment mode-based liquid crystal cell in which rod-shaped liquid crystal molecules are aligned in substantially opposite directions (symmetrically) between the upper part and the lower part of the liquid crystal cell. A liquid crystal display device using this liquid crystal cell based on the bend alignment mode has been disclosed in the specification of US Patent No. 4,583,825 or US Patent No. 5,410,422. Since the device is aligned symmetrically between the upper and lower parts of the liquid crystal cell, self-optical compensation is provided to the liquid crystal cell based on the bend orientation mode. Therefore, this liquid crystal mode is also referred to as an OCB (Optically Compensatory Bend) liquid crystal mode.

As for the liquid crystal cell based on the TN mode, the orientation of the liquid crystal cell based on the TN mode is also the case where rod-shaped liquid crystal molecules rise at the center of the cell and are located near the cell base.

[Liquid crystal display device based on VA mode]

In a liquid crystal cell based on the VA mode, rod-shaped liquid crystal molecules are substantially in a vertical alignment when no voltage is applied.

The VA-mode-based liquid crystal cell includes (1) a VA-mode-based liquid crystal cell in a narrow sense, in which rod-shaped liquid crystal molecules are aligned in a substantially vertical direction when no voltage is applied, and rod-shaped liquid crystal molecules are aligned in a substantially vertical direction when a voltage is applied. Upper horizontal orientation (described in JP-A-2-176625); (2) liquid crystal cell (MVA mode), wherein the VA mode is multi-domained to widen the viewing angle (described in Digest of tech.Papers (preliminary reports), 28,845, SID97 of (1997)); (3) liquid crystal cell (n-ASM mode), wherein the rod-shaped liquid crystal molecules are aligned in a substantially vertical direction when no voltage is applied, and the rod-shaped liquid crystal molecules are twisted more when a voltage is applied domain orientation (described in preliminary report on the discussion of the Japan liquid crystal Society, 58-59 (1998)); and (4) liquid crystal cells based on the Survival mode (published in LCD international 98).

[IPS mode-based liquid crystal display device]

A liquid crystal cell based on the IPS mode is a mode in which liquid crystal molecules are always rotated in a horizontal plane relative to a substrate and are oriented at an angle to an electrode axis when no electric field is applied. Applying an electric field will cause the liquid crystal molecules to face the electric field. The light transmittance can be changed by arranging the polarizers holding the liquid crystal cell at a predetermined angle. The liquid crystal molecules usable in the present invention are nematic liquid crystals having positive dielectric anisotropy Δε. The thickness (gap) of the liquid crystal layer is in the range of more than 2.8 μm to less than 4.5 μm. When the retardation Δn·d is in the range of more than 0.25 μm to less than 0.32 μm, light transmittance performance substantially free of long-wave dependence in the visible range is provided. When the liquid crystal molecules turn 45° from the rubbing direction to the electric field direction, the maximum light transmittance can be obtained by properly combining polarizers. Also, the thickness (gap) of the liquid crystal layer is controlled using polymer beads. Of course, glass beads, fibers and columnar resin spacers can be used to provide similar gaps. There are no particular restrictions on the liquid crystal molecules as long as they are nematic liquid crystals. A higher dielectric anisotropy Δε can further reduce the driving voltage, while a smaller refractive index dielectric anisotropy Δn can further increase the thickness (gap) of the liquid crystal layer, thereby reducing the liquid crystal sealing time and making the change of the gap smaller. Small.

[Other LCD Modes]

From a similar point of view as described above, the polarizing plate of the present invention can be provided to a liquid crystal display device based on an ECB mode or an STN mode.

Furthermore, the polarizer can be used in combination with a λ/4 plate as a polarizer for reflective liquid crystals or a surface protection plate for organic EL displays to reduce reflected light from the surface and inside.

The liquid crystal display element of the image display device that can be used in the present invention will be further described later in this specification.

The liquid crystal display element of the present invention is provided with polarizing plates respectively arranged at the upper end and the lower end of the liquid crystal cell formed by the two cell substrates, the polarizing plate is provided with a polarizing sheet and protective films respectively arranged at the upper end and the lower end of the polarizing sheet, and The lower end of the polarizing plate is provided with a brightness improving film.

The liquid crystal display element of the present invention comprises a transparent support on which an upper protective film of an upper polarizing plate is provided, and a low-refractive-index layer having an uppermost layer (outermost layer) forming the protective film and having a lower refractive index than the transparent support The antireflection film of , wherein the low refractive index layer contains at least one specific inorganic fine particle.

(LCD unit)

A cell substrate for forming a liquid crystal cell may include glass plates and plastic plates commonly used for the purpose, and those having a thickness of 0.5 mm or less are preferable in view of making the liquid crystal display element thinner.

In this case, there are no particular restrictions on the plastic plates as long as their transparency and mechanical strength are sufficiently large. Any known conventional plastic sheet can be used for this purpose. Resins forming the plastic sheet include thermoplastic resins such as polycarbonate, polyamide, polyethersulfone, polyester, polysulfone, polymethylmethacrylate, polyetherimide and polyamide, epoxy resins and thermosetting resins such as Unsaturated polyester, polydiallyl phthalate, polyisobutyl methacrylate. These resins may be used alone or in combination with other compounds or as a mixture.

"Characteristics of Antireflection Films"

An antireflection film having the aforementioned configuration can also be preferably used.

(optical properties)

When the angle of incidence is 5° under the wavelength of 450nm-650nm, the average value of the specular reflectance of the antireflection film (that is, the average reflectance ratio) is preferably 2.5% or less, more preferably 1.8% or less, even more Preferably 1.4% or less.

The above-mentioned specular reflectance at 5° of incidence is the ratio of the light intensity of light reflected by the sample at -5° from the normal direction to light radiated at +5° from the normal, which indicates the reflection at the back from the specular reflection the extent of the image. When used as an antireflection film having an antiglare function, light irradiated at an angle of -5° in the normal direction is weakened by scattered light to some extent resulting from surface unevenness imparting an antiglare function. Therefore, the specular reflectance can be used to determine the contribution reflecting the anti-glare function and the anti-reflection function.

When the average value of the specular reflectance at an incident angle of 5° in the antireflection film in the wavelength range of 450nm-650nm exceeds 2.5%, the reflected image on the back causes involvement and defects, such as on the surface of a polarizer for a display device Reduced visibility was observed when thin films were used. Therefore, this anti-reflection polarization is not preferred.

Considering the color of the specularly reflected light obtained from the 5° incident light of the CIE standard light source D65 at a wavelength of 380nm-780nm, where the L ^* , a ^* and b ^* values in the CIE1976L ^* a ^* b ^* color space are respectively in the following Within the range: 3≤L ^* ≤20, -7≤a ^* ≤7 and -10≤b ^* ≤10, the color of reflected light from red-purple to blue-purple can be reduced, which has always been the unrecognizable feature of conventional multilayer antireflection films. The problem solved, and when these values are in the range of 3≤L ^* ≤10, 0≤a ^* ≤5 and -7≤b ^* ≤0, the color of reflected light is significantly reduced, and bright light such as indoor fluorescent lights is slightly reflected The color of the ambient light is neutral, and it is not related to the application on the liquid crystal display device. Specifically, a range of a ^* > 7 makes the red color too strong, and a range of a ^* ≤ 7 makes the cyan color too strong, and thus are not preferable. In addition, a range of b ^* <-7 would make the blue color too strong, and a range of b ^* >0 would make the yellow color too strong, and thus are not preferable.

In the present invention, it is preferable that the above-mentioned respective values of L ^* , a ^* and b ^* are constant over the entire surface of the displayed image, and it is particularly preferable that the in-plane variation of these values is less than 15%. The in-plane rate of change refers to the percentage of the value obtained by subtracting the minimum value from the respective maximum value on the plane and dividing by the absolute value of the maximum value. More preferably, the in-plane variation rate is 10% or less. When the above values and rate of change are within these ranges, the displayed image has no change in antireflection performance and is excellent in visibility.

Specular reflectance and color were measured with a spectrophotometer V-550 (manufactured by JASCO Corporation) equipped with an adapter ARV-474. Specifically, the specular reflectance was measured at an incident angle of 5° and an output angle of 5°C in the wavelength range of 380-780 nm, and the average reflectance ratio in the wavelength range of 450-650 nm was calculated to evaluate antireflection performance. Also, the L ^* value, a* value, and ^{b* value} of the CIE 1976L ^* a ^* b ^* color space representing the color of the specularly reflected light of 5° incident light from the CIE standard illuminant D65 were calculated using the reflectance spectrum thus determined , so that the color of the reflected light can be evaluated.

By controlling the thickness of the transparent support to change (in particular, within ± 3.5) and by reducing the irregular thickness of each coating layer on the antireflective film to form an antireflective film, it is possible to greatly reduce the thickness caused by the irregular thickness of the antireflective film. The color change of the reflected light.

Makes the color of reflected light more neutral and provides excellent weather resistance.

The color of the reflected light is measured with reference to the reflection spectrum of the reflected light at 380-680 nm. The distance ΔE from the center of the L ^* a ^* b ^* chromaticity diagram is preferably 15 or less, more preferably 10 or less, most preferably 5 or less.

The change in ΔE of the above-mentioned antireflection film before and after the weathering test is preferably 15 or less, more preferably 10 or less, most preferably 5 or less.

Also, when the reflected light has such a color, it is preferable that the average reflectance ratio of the antireflection film in the wavelength range of 380-680 nm before and after the photostability test is changed by 0.5% or less.

When the value is within the above range, low reflection can be obtained while reducing the color of reflected light. Therefore, the color of ambient light that slightly reflects bright light such as indoor fluorescent lamps is made neutral, thereby preferably improving the quality of displayed images when used, for example, on the outermost surface of a graphic display device.

The above-mentioned antireflection film is characterized in that the optical characteristics and mechanical properties of the film are maintained within such an extent that no problem occurs after a weathering test. Specifically, the film is also characterized in that the change in the above-mentioned characteristics is maintained to a certain extent after the weathering test.

The weather resistance test refers to a treatment time at 50% RH and 150 hours using a sunlight weather resistance test chamber ["S-80", manufactured by Suga Test Instruments Co., Ltd.] according to JIS K-5600-7-7:1999 The tests carried out below.

An antireflection film having a neutral color of reflected light and a low reflectance ratio can be obtained by optimizing the refractive indices of the low-refractive-index layer and the high-refractive-index layer.

<Formation of upper polarizer>

The above-mentioned upper polarizing plate is preferably formed by adhering a polarizing sheet to the surface of the antireflection film on the transparent support side (on the observation side). The lower protective film of the upper polarizing plate is a transparent support, preferably a cellulose acylate film, more preferably the transparent support is adhered to the cellulose acylate film. In general, polarizing sheets are mainly composed of polyvinyl alcohol. Preferably, the surface of the transparent support is made hydrophilic by surface treatment in the same steps as described above, so as to improve the adhesive performance with the polarizing sheet. The transparent support as the lower protective film of the upper polarizer can be made hydrophilic by the same procedure.

Accordingly, the constructed polarizing plate can be used to provide a polarizing plate having an anti-reflection function and being excellent in physical strength and weather resistance, thereby reducing cost and making a display device thinner.

[Optical Compensation Film]

It is also preferred that the polarizing plate on the observation side of the present invention has an optical compensation film similar to that described above on the opposite support of the polarizing plate on which the antireflection film is fixed, so that the display image area on the liquid crystal display device can be widened. perspective.

[Lower polarizer]

The lower polarizer (polarizer on the backlight side) of the liquid crystal cell of the present invention is provided together with a brightness improving film on the side of the protective film (transparent carrier) opposite to the adjacent side (backlight/low end) of the liquid crystal cell . A more preferable embodiment is an embodiment in which an optical compensation film, ie, an optical compensation film/polarizing plate/brightness improvement film is provided on the protective film adjacent to the liquid crystal cell.

Here, the polarizing plate and the optical compensation film are the same as those described above for the viewing side polarizing plate (upper polarizing plate).

(Brightness Improvement Film)

There is no particular limitation on the brightness improving film used in the present invention as long as it separates natural light into transmitted light and reflected light. For example, the film may include films that separate natural light into transmitted light (as linearly polarized light) and reflected light that can be reused as circularly polarized light, and films that transmit linearly polarized light of a certain polarization axis but reflect other light.

When the back light is incident through the polarizing sheet from the back of the liquid crystal cell, if the brightness improving film is not used, most of the light whose polarization direction does not coincide with the polarizing axis of the polarizing sheet is absorbed by the polarizing sheet and does not pass through the polarizing sheet. That is, about 50% of the light is absorbed by the polarizing sheet, depending on the properties of the polarizing sheet used, with the result that less light is used to create a liquid crystal image or other image resulting in a darker image. The brightness improving film can effectively utilize light such as back light to display an image of a liquid crystal display device and make the image side brighter because light having a polarization direction that can be absorbed by a polarizing sheet can be reflected on the brightness improving film at one time, Not incident on the polarizing sheet, the light then travels backwards through a reflective layer or other layer provided on the back side, whereby the light again strikes the brightness improving plate, and the process repeats, whereby between the brightness improving film and the brightness improving plate The reflected and reversed light is converted into light having a polarization direction that can pass through the polarizing film, and this polarized light is transmitted and supplied to the polarizing sheet.

Brightness improving films include films that transmit linearly polarized light of a certain polarization axis but reflect other light such as multilayer films of dielectric materials and multilayer laminates of films with different refractive index anisotropy, either reflecting clockwise or counterclockwise Films that circulate polarized light such as cholesteric liquid crystal layers, specifically, oriented films of cholesteric liquid crystal polymers and films in which an oriented liquid crystal layer is supported on a film substrate.

The aforementioned brightness-improving film that transmits linearly polarized light of a certain polarization axis makes the transmitted light incident on the polarizer while keeping the polarization axis uniform, thereby reducing absorption loss caused by the polarizer and achieving efficient transmission. A brightness-improving film that transmits circularly polarized light, such as a cholesteric liquid crystal layer, actually makes light incident on the polarizing sheet as well. However, such incidence on the polarizing plate after the transmitted circularly polarized light is converted into linearly polarized light by the retardation plate is preferable in view of reducing absorption loss. Therefore, using a λ/4 plate as a retardation plate can efficiently convert circularly polarized light into linearly polarized light. As examples, see those described in JP-A-2003-227933.

Brightness improving films such as multilayer films of dielectric substances and thin film multilayer laminates with different refractive index anisotropy are commercially available from 3M Ltd. (D-BEF), or cholesteric liquid crystal layers (specifically, Aligned films of cholesteric liquid crystal polymers) and films in which an aligned liquid crystal layer is supported on a film substrate are commercially available from Nittodenko Co., Ltd. ("PCF") and Merck Inc. ("Transmax").

As explained above, since the liquid crystal display element of the present invention has an upper polarizing plate above the liquid crystal cell and a lower polarizing plate under the liquid crystal cell, it is excellent in physical strength and weather resistance, has an anti-reflection function, is clear, has excellent visibility, and is thinner , lighter and less expensive. (display device)

The liquid crystal display device can be assembled according to conventional procedures. That is, in general, a liquid crystal display device is composed of a liquid crystal cell, an optical film, and other components such as an illumination system and a driving circuit as necessary in appropriate combinations. The display device of the present invention is not particularly limited as long as the liquid crystal display element of the present invention is used.

In the assembly of a liquid crystal display device, for example, components such as a prism array, a lens array sheet, a light diffusion plate, a light guide plate and a backlight may be properly arranged in one layer or in two or more layers at appropriate positions.

Example

The present invention will be described in detail with reference to the following examples. However, it should be construed that the present invention is not limited to these Examples. Parts and percentages are by weight unless otherwise indicated.

<Example A>

(Synthesis of perfluoroolefin copolymer (1))

Perfluoroolefin Copolymer(1)

(50:50 means molar ratio)

Add 40 mL of ethyl acetate, 14.7 g of hydroxyethyl butyl ether, and 0.55 g of dilauroyl peroxide into a 100 mL volume stainless steel autoclave equipped with a stirrer, and evacuate all remaining air in the system and replace it with nitrogen. replace. Furthermore, 25 g of hexafluoropropylene (HFP) was charged into the autoclave, and the temperature was raised to 65°C. When the temperature in the autoclave reaches 65°C, the pressure is 0.53MPa. The reaction was continued at this temperature for 8 hours, heating was stopped when the pressure dropped to 0.31 MPa, and then cooled. When the temperature in the autoclave was lowered to room temperature, the autoclave was opened, the unreacted monomer was evacuated, and the reaction solution was collected. The obtained reaction solution was then added to excess hexane, the solvent was removed by decantation and the deposited polymer was collected. Then, the polymer was dissolved in a small amount of ethyl acetate to conduct hexane precipitation twice, whereby the remaining monomers were completely removed. After drying, 28 g of polymer were obtained. Then, 20 g of the polymer was dissolved in 100 ml of N,N-dimethylacetamide, 11.4 g of acryloyl chloride was added dropwise thereto, and the reaction liquid was stirred at room temperature for 10 hours while cooling with ice. Ethyl acetate was added to the reaction liquid, washed with water and concentrated after extracting the organic layer. The obtained polymer was then precipitated with hexane to obtain 19 g of perfluoroolefin copolymer (1). The refractive index of the polymer is 1.421.

(preparation of sol solution a)

120 parts of methyl ethyl ketone, 100 parts of acryloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.), ethyl acetoacetate diisopropoxyaluminum ( Trade name: Kerope EP-12, manufactured by Hope Chemical Co., Ltd.) 3 parts were added to a reaction vessel equipped with a stirrer and a reflux condenser, and mixed. Then, 30 parts of ion-exchanged water was added, the resultant was reacted at 60° C. for 4 hours, and cooled to room temperature to obtain a sol solution a. Its weight-average molecular weight is 1600, which is higher than that of the oligomer compound, and the compound with a molecular weight of 1000-20000 is 100%. Gas chromatography confirmed that no acryloxypropyltrimethoxysilane remained in the starting material.

(Preparation of Coating Liquid A for Hard Coating)

PET-30 50.0 parts by weight

Irgacure 184 2.0 parts by weight

SX-350(30%) 1.7 parts by weight

Cross Acryl/Styrene Granules (30%) 13.3 parts by weight

FP-132 0.75 parts by weight

KBM-5103 10.0 parts by weight

Toluene 38.5 parts by weight

(Preparation of Coating Liquid B for Hard Coating)

Desolite Z7404 (hard coating containing zirconia fine particles 100 parts by weight

compound solution, manufactured by JSR)

DPHA (ultraviolet curing resin: Nippon Kayaku 31 parts by weight

Co., Ltd.)

KBM-5103 10 parts by weight

KE-P150 (1.5μm silica particles: Nippon 8.9 parts by weight

Shokubai Co., Ltd.)

MXS-300 (3μm cross-linked PMMA particles: Soken 3.4 parts by weight

Chemical & Engineering Co., Ltd.)

MEK (methyl ethyl ketone) 29 parts by weight

MIBX (methyl isobutyl ketone) 13 parts by weight

(Preparation of coating solution C for hard coat layer)

Add 270.0 parts by weight of poly(glycidyl methacrylate) with a weight average molecular weight of 15000, 730.0 parts by weight of methyl ethyl ketone, 500.0 parts by weight of cyclohexanone and 50.0 parts by weight of a photopolymerization initiator (Irgacure 184, Ciba Specialty Chemicals) into 750.0 parts by weight of trimethylolpropane triacrylate (TMPTA, Nippon Kayaku Co., Ltd.) and mixed.

The above coating solutions A and B were filtered through a polypropylene filter with a pore size of 30 μm, and the solution C was filtered through a polypropylene filter with a pore size of 0.4 μm to prepare each coating solution for the hard coat layer.

(Preparation of Titanium Dioxide Fine Particle Dispersion)

As titanium dioxide fine particles, titanium dioxide fine particles (MPT-129C, IshiharaSangyo Kaisha Ltd. _{TIO 2} : Co ₃ O ₄ : Al ₂ O _{3 :} ZrO ₂ =90.5:3.0:4.0:0.5 weight ratio) containing cobalt and subjected to Surface treatment with aluminum hydroxide and zirconium hydroxide.

41.1 parts by weight of the following dispersant and 701.8 parts by weight of cyclohexanone were added to 257.1 parts by weight of the above particles, and the resultant was dispersed using a bead mill to prepare a titanium dioxide dispersion having a weight average pore diameter of 70 nm.

(Preparation of Coating Solution A for Middle Refractive Index Layer)

68.0 parts by weight of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA), 3.6 parts by weight of a photopolymerization initiator (Irgacure 907, Ciba Specialty Chemicals), a sensitizer (Kayacure-DETX, Nippon Kayaku Co., Ltd. .) 1.2 parts by weight, 279.6 parts by weight of methyl ethyl ketone and 1049.0 parts by weight of cyclohexanone were added to 99.1 parts by weight of the above titanium dioxide dispersion and stirred. After thorough stirring, the resultant was filtered through a polypropylene filter with a pore size of 0.4 µm.

(Preparation of Coating Solution A for High Refractive Index Layer)

40.0 parts by weight of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, Nippon Kayaku Co., Ltd.), 3.3 parts by weight of a photopolymerization initiator (Irgacure907, Ciba Specialty Chemicals), a sensitizer (Kayacure- DETX, Nippon Kayaku Co., Ltd.) 1.1 parts by weight, 526.2 parts by weight of methyl ethyl ketone and 459.6 parts by weight of cyclohexanone were added to 469.8 parts by weight of the above-mentioned titanium dioxide dispersion A, and stirred. The resultant was filtered through a polypropylene filter with a pore size of 0.4 µm.

(Preparation of Coating Solution A for Low Refractive Index Layer)

DPHA 4.0 parts by weight

Hollow silica (18.2%) 40.0 parts by weight

Irgacure 907 0.2 parts by weight

Sol solution a 6.2 parts by weight

MEK 299.6 parts by weight

(Preparation of Coating Solution B for Low Refractive Index Layer)

DPHA 3.3 parts by weight

Hollow silica (18.2%) 40.0 parts by weight

RMS-033 0.7 parts by weight

Irgacure 907 0.2 parts by weight

Sol solution a 6.2 parts by weight

MEK 299.6 parts by weight

(Preparation of Coating Solution C for Low Refractive Index Layer)

JTA113(6%) 13.0 parts by weight

MEK-ST-L 1.3 parts by weight

Sol solution a 0.6 parts by weight

MEK 5.0 parts by weight

Cyclohexanone 0.6 parts by weight

(Preparation of Coating Solution D for Low Refractive Index Layer)

JN7228A(6%) 13.0 parts by weight

MEK-ST-L 1.3 parts by weight

Sol solution a 0.6 parts by weight

MEK 5.0 parts by weight

Cyclohexanone 0.6 parts by weight

(Preparation of Coating Liquid E for Low Refractive Index Layer)

JN7228A(6%) 100.0 parts by weight

MEK-ST 4.3 parts by weight

MEK-ST-L 5.1 parts by weight

Sol solution a 2.2 parts by weight

MEK 15.0 parts by weight

Cyclohexanone 3.6 parts by weight

(Preparation of Coating Liquid F for Low Refractive Index Layer)

Example compound; P-1 14.0 parts by weight

X-22-164C 0.42 parts by weight

Irgacure 907 0.7 parts by weight

MIBK 84.7 parts by weight

(Preparation of Coating Liquid G for Low Refractive Index Layer)

Put 30 parts by weight of tetramethoxysilane and 240 parts by weight of methanol into a 4-neck reaction flask and stir, the temperature of the solution is kept at 30°C, and add 2 parts by weight of nitric acid to 6 parts by weight of water. The solution. The resultant was stirred at 30° C. for 5 hours to obtain an alcohol solution (solution A) of a siloxane oligomer. The siloxane oligomer had a relative molecular weight of 950 in terms of ethylene glycol/polyethylene oxide as measured by GPC.

In the separation step, 300 parts by weight of methanol was added to a 4-neck reaction flask, and then mixed with 30 parts by weight of oxalic acid under stirring. Then, the obtained solution was heated under reflux, and 30 parts by weight of tetramethoxysilane and 8 parts by weight of tridecafluorooctyltrimethoxysilane were added thereto. The resultant was heated under reflux for 5 hours and cooled to obtain a fluorine compound solution (solution B) having a fluoroalkyl structure and a polysiloxane structure.

30 parts by weight of solution A and 100 parts by weight of solution B were mixed and diluted with butyl acetate so that the dry solid concentration in the coating mixture solution was 1% by weight, thereby obtaining coating liquid G for a low refractive index layer.

(Preparation of Coating Liquid H for Low Refractive Index Layer)

Solution A and Solution B were prepared similarly to Coating Solution G for the low-refractive index layer, and 1 part by weight of polydimethylsiloxane DMS-H21 (manufactured by Gelest) having hydrogen terminal groups and 80 parts by weight Hollow silica particles (18.2%) described later were added to 30 parts by weight of solution A and 100 parts by weight of solution B, and mixed. The resultant was diluted with butyl acetate so that the dry solid concentration in the coating mixture solution was 1% by weight, thereby obtaining a coating solution H for a low refractive index layer.

The above solution was stirred, and then filtered through a polypropylene filter with a pore diameter of 1 μm to prepare a coating liquid for a low refractive index layer.

The following are other compounds used in the present invention (their detailed descriptions are omitted in this specification).

PET-30: a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (manufactured by Nippon Kayaku Co., Ltd.)

Irgacure 184: Polymerization initiator (manufactured by Ciba Specialty Chemicals)

SX-350: Cross-linked polystyrene particles with an average particle diameter of 3.5 μm (refractive index 1.60, manufactured by Soken Chemical & Engineering Co., Ltd, using 30% toluene dispersion, dispersed by Polytron dispersing equipment at 10000 rpm for 20 minutes used later)

Crossed acryl/styrene particles: average particle diameter 3.5 μm (refractive index 1.55, manufactured by Soken Chemical & Engineering Co., Ltd., 30% toluene dispersion)

FP-132: Fluorine Surface Modifier

KBM-5103: Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.)

JN7228A: Thermally crosslinked fluoropolymer (refractive index 1.42; dry solids concentration 6%; manufactured by JSR), trade name: Opstar JN-7228A

JTA 113: thermally crosslinked fluoropolymer (refractive index 1.44; dry solids concentration 6%; manufactured by JSR), trade name: Opstar JTA-113

P-1: Perfluoroolefin Copolymer (1)

DPHA: Mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (Nippon Kayaku Co., Ltd.)

MEK-ST-L: silica sol (silicon dioxide, MEK-ST with different particle diameters; average particle diameter 45 nm; dry solid concentration 30%; manufactured by Nissan Chemical Industries Ltd.)

Hollow silica: KBM-5103 surface-modified hollow silica sol (CS-60 (trade name), manufactured by Catalysts & Chemicals Industries Co., Ltd.; refractive index 1.31; average particle diameter 60 nm; shell thickness 10 nm; pores rate 58%; dry solid concentration 20% surface treated by KBM-5103 so that the surface treated silicon dioxide content is 30% by weight; dry solid concentration 18.2%)

KF96-1000CS: straight polysiloxane (Shin-Etsu Chemical Co., Ltd.)

X22-164C: Reactive polysiloxane (Shin-Etsu Chemical Co., Ltd.)

RMS-033: Reactive polysiloxane (Gelest)

R-2020: Fluoroalkyl Acrylate Monomer (Daikin Industries Ltd.)

R-3833: Fluoroalkyl Acrylate Monomer (Daikin Industries Ltd.)

FMS-121: Fluoroalkylpolysiloxane (Gelest)

Irgacure 907: Photopolymerization initiator (Ciba Specialty Chemicals)

[Example A-1]

(1-1): Coating of Hard Coat A and Hard Coat C

A triacetyl cellulose film (TD80U, manufactured by Fuji Photo Film Co., Ltd.) was unrolled in a roll form as a support, and a film having a diameter of 50 mm and a gravure pattern of 180 lines/inch and a depth of 40 μm was used thereon. Micro-gravure roller and transfer speed are the coating solution of above-mentioned hard coating directly coated with the doctor blade of 30m/min, at 60 ℃, dry 150 seconds, then, use air-cooled metal halide lamp (by Eye Graphics Co., Ltd. .manufacturing) (160W/cm) radiates ultraviolet rays with a brightness of 400mW/cm ² , the radiation is 250mJ/cm ² for hard coat A, and the radiation is 300mJ/cm ² for hard coat C, nitrogen flushing is performed The coating was cured so as to obtain an oxygen concentration of 1.0% by volume or less to form a hard coating, and then rolled. After curing, the number of rotations of the gravure roll was adjusted so that the thickness of the hard coat layer A was 6 μm and the thickness of the hard coat layer C was 8 μm.

(1-2): Coating of hard coat B

A triacetyl cellulose film (TD80U, manufactured by Fuji Photo Film Co., Ltd.) was unrolled in a roll form as a support, and a film having a diameter of 50 mm and a gravure pattern of 135 lines/inch and a depth of 60 μm was used thereon. Micro-gravure roller and transfer speed are the coating solution of above-mentioned hard coat layer directly coated with the doctor blade of 10m/min, dry 150 seconds at 60 ℃, then, use air-cooled metal halide lamp (by Eye Graphics Co., Ltd. .manufacturing) (160W/cm) radiates ultraviolet light at a brightness of 400mW/cm ² , the radiation is 250mJ/cm ² , nitrogen flushing is performed to obtain an oxygen concentration of 1.0% by volume or less, thereby curing the coating to form a hard coating Layer, then roll up. After curing, the number of rotations of the gravure roll was adjusted so that the thickness of the hard coat layer was 3.6 μm.

(2) Coating of medium refractive index layer A

The triacetyl cellulose film (TD80U, manufactured by FujiPhoto Film Co., Ltd.) coated therein up to the hard coat layer was developed again, and a diameter of 50 mm with 180 lines/inch and a depth of 40 μm was used thereon. The gravure pattern of the micro-gravure roll and doctor blade coating medium refractive index layer of the coating solution. The drying process was performed at 90°C for 30 seconds, and ultraviolet rays were irradiated at a brightness of 400mW/cm2 using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) (180W/ ^cm2 ), and the radiation was 400mJ /cm ² , nitrogen flushing was performed to obtain an oxygen concentration of 1.0% by volume or less. The number of rotations of the gravure roll was adjusted so that the thickness after coating was 67 nm, thereby providing a medium refractive index layer, which was then rolled up. The refractive index of the medium refractive index layer after curing was 1.630.

(3) Coating of high refractive index layer A

The triacetyl cellulose film (TD80U, manufactured by Fuji Photo Film Co., Ltd.) coated therein with up to a medium refractive index layer was developed again, and a film having a diameter of 50 mm and with 180 lines/inch and A microgravure roll and a doctor blade of a gravure pattern with a depth of 40 μm were used to coat the coating liquid for the high refractive index layer. The drying process was performed at 90°C for 30 seconds, and ultraviolet rays were irradiated at a brightness of 600mW/cm2 using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) (240W/ ^cm2 ), and the radiation was 400mJ /cm ² , nitrogen flushing was performed to obtain an oxygen concentration of 1.0% by volume or less. The number of rotations of the gravure roll was adjusted so that the thickness after coating was 107 nm, thereby providing a high refractive index layer, which was then rolled up. The refractive index of the high refractive index layer after curing was 1.905.

(4-1) Coating of low refractive index layer [coating and curing process A]

The triacetyl cellulose film coated therein up to the hard coat layer or the high refractive index layer was unrolled again, on which a microgravure roll with a diameter of 50 mm and a gravure pattern of 180 lines/inch and a depth of 40 μm was used and The above coating solution for the low refractive index layer was coated with a doctor blade at a transfer speed of 15 m/min, and the first drying was performed at 120° C. for 150 seconds and the second drying was performed at 140° C. for 8 minutes. Then, using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) (240 W/cm) to irradiate ultraviolet rays at a brightness of 400 mW/cm ² , the radiation was 900 mJ/cm ² , nitrogen flushing was performed to obtain an oxygen concentration 1.0% by volume or less. The number of rotations of the gravure roll was adjusted so that the thickness was 100 nm, thereby providing a low-refractive index layer, which was then rolled up.

(4-2) Coating of low refractive index layer [coating and curing process B]

The coating of the low-refractive index layer was performed similarly to [Coating and Curing Process A], except that the second drying was not performed.

(4-3) Coating of low refractive index layer [coating and curing process C]

The above-prepared coating liquid for the low-refractive index layer was coated using a wire bar so that the thickness after curing was about 100 nm, and the resultant was thermally cured at 90° C. for 1 hour to form an antireflection layer.

(4-4) Coating of low refractive index layer [coating and curing process D]

The triacetyl cellulose film coated up to the hard coat layer was unrolled again, and the above coating liquid for the low refractive index layer was coated thereon by a die coating method at a transfer speed of 25 m/min. The resultant was dried at 120°C for 150 seconds and then at 140°C for 8 minutes. Using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) (240 W/cm) to irradiate ultraviolet light at a brightness of 400 mW/cm ² , the radiation was 900 mJ/cm ² , nitrogen flushing was performed to obtain an oxygen concentration of 1.0 vol. % or less. The number of rotations of the gravure roll was adjusted so that the thickness was 100 nm, thereby providing a low-refractive index layer, which was then rolled up.

(Preparation of anti-reflective film samples)

As shown in Tables 1-3, antireflection film samples were prepared according to the above method.

Table 1 sample number low refractive index layer hard coat Remark Coating solution Changes from Initial Coating Fluid Hollow silica particles Surface free energy reducing compounds/binders Coating and Curing Methods 001 C none No have A A comparative example 002 A none have No B A comparative example 003 B none have have B A this invention 004 B Changed from RMS-033 to X22-164 on the basis of equal weight have have B A this invention 005 B Changed from RMS-033 to KF96-1000CS on the basis of equal weight have have B A this invention 006 B Changed from RMS-033 to FMS121 on the basis of equal weight have have B A this invention 007 B RMA-033 = 0.35 parts by weight DPHA = 3.65 parts by weight have have B A this invention 008 A Add R2020=1.0 parts by weight DPHA=3.0 parts by weight have have B A this invention 009 A Add R-3833=1.6 parts by weight DPHA=2.4 parts by weight have have B A this invention 010 B PHA=5.8 parts by weight, no sol solution a, MEK=295.9 parts by weight have have B A this invention 011 B Add R-2020=0.83 parts by weight DPHA=2.47 parts by weight have have B A this invention 012 B none have have D. A this invention 013 D. none No have A A comparative example

Table 2 sample number low refractive index layer hard coat Remark Coating solution Changes from Initial Coating Fluid Hollow silica particles Surface free energy reducing compounds/binders Coating and Consolidation Methods 101 G none No No C A comparative example 102 h none have have C A this invention 103 A DPHA=0 parts by weight, JTA113 (6%)=66.7 parts by weight, MEK=236.9 parts by weight have have A A this invention 104 A DPHA = 0 parts by weight, exemplary compound; P-1 = 4.0 parts by weight have have B A this invention 105 A DPHA=0.8 parts by weight, example compound; P-1=3.2 parts by weight have have B A this invention 106 B DPHA=0.7 parts by weight, example compound; P-1=2.6 parts by weight have have B A this invention 107 B DPHA=0.7 parts by weight, exemplary compound; P-20=2.6 parts by weight have have B A this invention 108 B DPHA=0.7 parts by weight, example compound; P-3=2.6 parts by weight have have B A this invention 109 B DPHA=0.7 parts by weight, example compound; P-1=2.6 parts by weight have have D. A this invention

table 3 sample number low refractive index layer high refractive index layer middle index layer hard coat Remark Coating solution Hollow silica particles Surface free energy reducing compounds/binders Coating and Consolidation Methods 201 E. No have A No No B comparative example 202 B have have B No No B this invention 203 Similar to the coating solution used to prepare sample 011 have have B No No B this invention 204 Similar to the coating solution used to prepare sample 106 have have B No No B this invention 205 f No have B A A C comparative example 206 B have have B A A C this invention 207 Similar to the coating solution used to prepare sample 011 have have B A A C this invention 208 Similar to the coating solution used to prepare sample 106 have have B A A C this invention

(saponification of anti-reflective film)

After the film formation, the samples other than samples 101 and 102 were subjected to the following treatments.

A 1.5 mol/l sodium hydroxide solution was prepared and kept at 55°C. A 0.01 mol/l dilute sulfuric acid solution was prepared and kept at 35°C. The prepared antireflection film was soaked in the above sodium hydroxide for 2 minutes, and soaked in water to completely rinse off the sodium hydroxide solution. After soaking in the above dilute sulfuric acid solution for 1 minute, the film sample was soaked in water to completely rinse off the dilute sulfuric acid solution. Finally, the samples were fully dried at 120 °C.

(Evaluation of anti-reflection film)

The film samples obtained after saponification were evaluated for the following items, however, samples 101 and 102 were unsaponified samples and evaluated for the following items.

(1) Average reflectance ratio

The spectral reflectance ratio at an incident angle of 5° in the wavelength range of 380-780 nm was measured using a spectrophotometer (manufactured by JASCO). The result was used to calculate the average reflectance ratio in the wavelength range of 450-650 nm.

(2) Evaluation of scratch resistance of steel wool

A friction test was performed using a friction tester under the following conditions.

Condition: 25℃, 60%RH

Material to be rubbed: Steel wool (Gerede No. 0000, manufactured by Nihon Steel Wool Co., Ltd.) was wrapped around the rubbing head of the measuring instrument to be in contact with the sample (1 cm x 1 cm), and fixed with a tape.

Moving distance (one way): 13cm

Friction speed: 13cm/sec

Load: 500g/cm ²

Head contact area: 1cm×1cm

Friction times: 10 reciprocating movements

Oil-based black ink was applied to the back of the rubbing material, and observed through a magnifying glass under reflected light, and the rubbing portion was evaluated on the basis of the following criteria.

AA: After very careful observation, no abrasions were observed at all

A: After very careful observation, slight scratches were observed

AB: Slight abrasions observed

B: Moderate abrasion observed

BC-C: Abrasions are observed at a glance

(3) Evaluation of adhesiveness

A utility knife was used to cut 11 vertical lines and 11 horizontal lines on the surface of the antireflection film having the low-refractive index layer, thereby making a total of 100 squares. The adhesion test was carried out by pressing a polyester adhesive tape (No. 31B) manufactured by Nitto Denko Co., Ltd. at the same point repeatedly 3 times. Observe with a magnifying glass whether the tape is peeled off, and perform the following 4-level evaluation.

AA: In 100 squares, no peeling was found at all

A: Out of 100 squares, less than 2 squares are stripped

B: Out of 100 squares, 3-10 squares are stripped

C: Out of 100 squares, more than 10 squares were stripped

(4) Rubber friction resistance

The antireflective film was fixed on the surface of the glass plate using an adhesive, and an eraser (trade name: MONO, manufactured by Tombo Pencil Co., Ltd.) with a hollow diameter of 8 mm and a thickness of 4 mm was used as a rubbing head of a tribometer , that is, under a load of 500g/ ^cm2 , the rubber is pressed vertically on the surface of the anti-reflection film from above, and then, at 25°C and 60RH%, pass through 200 reciprocating friction movement. After that, the eraser was removed and the rubbed part of the sample was confirmed by a magnifying glass. The test was repeated 3 times, and the results were averaged and evaluated on the following 4 levels.

A: Almost no scratches were found

B: Slight scratches were found

C: Clear scratches were found

CC: Scratches found throughout the surface

(5) Felt pen wipe resistance

The antireflection film was fixed on the surface of the glass plate with an adhesive and a circle 3 with a diameter of 5 mm was drawn with the tip of a felt pen (black ink, trade name: "Makky Gokuboso", manufactured by ZEBRA) at 25° C. and 60 RH%. Second-rate. After 5 seconds, the circle was wiped 20 times in a reciprocating manner with a cloth folded 10 times (trade name: "Vencot", manufactured by Asahi Chemical Industry Co., Ltd.) under a load that bends a bundle of Vencot. Repeat the above steps of drawing circles and wiping under the same conditions until the circles drawn with a felt pen can no longer be erased after wiping, and count the number of times the circles are successfully wiped off. The above test was repeated 4 times and the results were averaged for the following 4' level evaluation.

A: The circle can be wiped more than 10 times

B: The circle can be wiped several times to less than 10 times

C: The circle can only be wiped once

CC: The circle cannot be erased at any time

(6) Evaluation of surface segregation of silicon (Si atom) and fluoroalkyl group (F atom)

Measured using ESCA-3400 (manufactured by Shimadzu Corp.) on the outermost surface of a single antireflection film under the conditions (vacuum degree, 1×10 ⁻⁵ Pa; X-ray source, target Mg; voltage, 12 kV; current, 20 mA) The intensity ratio of the photoelectron spectra of Si2p, Fls, and Cls, Si2p/Cls (=Si(a)) to Fls/Cls (=F(a)), was obtained using an ESCA-3400 (ion gun; voltage, 2 kV; current , 20mA) ion etching equipment measures the intensity ratio of the photoelectron spectrum from 1/5 (± 5%) of the thickness to the bottom layer at the bottom of the 80% distance from the surface of the low refractive index layer, Si2p/Cls (=Si(b)) The ratio Fls/Cls (=F(a)), from which changes in intensity ratios before and after etching, Si(a)/Si(b) and F(a)/F(b) are determined. Then, with the single change of Si2p/Cls ratio and Fls/Cls ratio before and after etching (intensity ratio of the photoelectron spectrum of the outermost surface of the low-refractive index layer/from the low-refractive-index layer surface down 80% of the bottom layer The following three-level evaluation was performed based on the change in the intensity ratio of the photoelectron spectrum. The above measurements are carried out at 3 locations on the same film at least 2 cm apart from each other.

AA: Intensity ratio increase greater than 5 times after etching in greater than 1 position

A: The intensity ratio after etching at more than 1 location is increased by less than 5 times and more than 3 times;

B: The intensity ratio after etching at more than 1 location is increased by less than 3 times and more than 1.5 times;

-: The intensity ratio after etching is increased by less than 1.5 times.

The intensities Fls and Cls at the peaks of the respective photoelectron spectra were determined. The intensity Si2p at the peak derived from polysiloxane (Si atom of polydimethylsiloxane) with a binding energy of about 105 eV was determined and used to calculate the above intensity ratio and compare it with that obtained from inorganic silica The Si atoms of the particles are different. Preliminary tests were carried out under different etching conditions. The surface of the low-refractive index layer was gradually polished to evaluate the etching conditions under the hard coat layer or the high-refractive index layer to an extent of 80% downward from the surface. The assays described above were performed after the pilot study.

Table 4 sample number Average Specular Reflectance (%) Average aggregate reflectance coefficient (%) Surface free energy: γs ^v (mN/m) Rubber friction resistance felt pen rub resistance Steel wool scratch resistance Crosscut Adhesion ESCA strength ratio between upper and lower parts Remark Si/C F/C 001 2.0 2.9 twenty two B B B A A A comparative example 002 1.6 2.6 44 A C A C - - comparative example 003 1.6 2.6 twenty one A AAA AAA AAA AAA - this invention 004 1.6 2.6 twenty two A A AAA AAA AAA - this invention 005 1.6 2.6 twenty three A B A AAA AAA - this invention 006 1.6 2.6 twenty three A A A A AAA AAA this invention 007 1.6 2.6 twenty three A A AAA AAA AAA A this invention 008 1.4 2.4 27 A B A A - AAA this invention 009 1.4 2.4 30 A B A A - AAA this invention 010 1.7 2.7 twenty two B A B B AAA - this invention 011 1.4 2.4 19 A AAA AAA AAA AAA AAA this invention 012 1.6 2.6 twenty one A A AAA AAA AAA - this invention 013 1.8 2.8 twenty one CC AAA B B A A comparative example

table 5 sample number Average Specular Reflectance (%) Average aggregate reflectance coefficient (%) Surface free energy: γs ^v (mN/m) Rubber friction resistance felt pen rub resistance Steel wool scratch resistance Crosscut Adhesion ESCA strength ratio between upper and lower parts Remark Si/C F/C 101 1.7 2.7 43 C C CC A A - comparative example 102 1.5 2.5 25 B A B AAA AAA - this invention 103 1.3 2.3 twenty two B AAA B A A A this invention 104 1.4 2.4 25 B B A A - A this invention 105 1.5 2.5 30 A B A A - A this invention 106 1.5 2.5 twenty two B AAA AAA AAA AAA A this invention 107 1.5 2.5 twenty three B A A AAA AAA A this invention 108 1.5 2.5 twenty two B A A AAA AAA A this invention 109 1.5 2.5 twenty two A A AAA AAA AAA A this invention

Table 6 sample number Average Specular Reflectance (%) Average aggregate reflectance coefficient (%) Surface free energy: γs ^v (mN/m) Rubber friction resistance felt pen rub resistance Steel wool scratch resistance Crosscut Adhesion ESCA strength ratio between upper and lower parts Remark Si/C F/C 201 1.4 1.9 twenty one CC A C A A A comparative example 202 1.3 1.8 twenty one A A A AAA AAA - this invention 203 1.3 1.8 19 A A A AAA AAA AAA this invention 204 1.4 2.4 twenty two B B A AAA AAA A this invention 205 0.5 0.5 twenty three CC C B C A A comparative example 206 0.4 0.4 twenty one A A A AAA AAA - this invention 207 0.4 0.4 20 A A A AAA A AAA this invention 208 0.4 0.4 twenty two B B A AAA AAA A this invention

The results obtained from Tables 4-6 clearly confirm the following.

The antireflection film of the present invention satisfies all reflectance ratios, scratch resistance, felt pen rub resistance, and adhesiveness to a satisfactory degree, and is improved in every aspect as an antireflection film. All samples of the invention achieve low reflection compared to sample 001. Samples 003, 008 and 011 obtained by adding polysiloxane and fluoroalkyl compound to sample 002 were improved in felt pen rub resistance. Also, samples 103 and 106, which used a combination of polysiloxane and fluorine, exhibited better felt pen rub resistance.

[Example A-2]

Then, the sample film of the present invention described in Example 1 was adhered to a polarizing plate to prepare a polarizing plate having an antireflection function. Using the polarizing plate, a liquid crystal display device in which an antireflection layer is arranged on the outermost surface, which has less reflection of external light, less conspicuous reflected images and excellent visibility, was prepared. This device satisfies all the requirements for stain resistance, dust resistance, and film strength that are problematic in actual use.

[Example A-3]

80 μM thick triacetyl cellulose film (TAC-TD80U, Fuji Photo Film Co., Ltd.), soaked in NaOH solution (1.5 mol/l and 55 °C) for 2 min, neutralized and washed with water, and placed on A triacetyl cellulose film coated with the sample of the present invention prepared in Example 1 was adhered to both sides of a polarizing sheet prepared by stretching, and after iodine was adsorbed on polyvinyl alcohol, the resultant was then protected. processed to produce a polarizer. Therefore use the prepared polarizer so that the anti-reflection film face is arranged on the outermost surface, instead of the polarizer on the observation side (with a polarization separation layer) used in the liquid crystal display device of the notebook computer equipped with the transmissive TN liquid crystal display device A polarization separation film (D-BEF, manufactured by Sumitomo 3M) is sandwiched between the backlight and the liquid crystal cell). The display device described above provides extremely small background reflections and relatively excellent display quality.

[Example A-4]

A sample of the invention as described in Example 1 was adhered to the protective film on the liquid crystal cell side of the polarizer on the viewing side of a transmissive TN liquid crystal cell, and to the liquid crystal cell of the polarizer on the backlight. On the protective film, it was used for a viewing angle widening film (wide viewing angle film SA 12B, manufactured by Fuji Photo Film Co., Ltd.). The liquid crystal display device constructed as described above provides excellent contrast in a bright room, a very wide viewing angle in every respect, considerably excellent visibility, and high display quality.

[Example A-5]

The sample of the present invention described in Example 1 was adhered to a glass plate of an organic EL display device with an adhesive. A display of this construction provides lower reflection from the glass surface, higher visibility and satisfactory stain resistance from fingerprints or dust.

[Example A-6]

A polarizing plate provided with an antireflection film on only one side was prepared using the sample of the present invention described in Example 1, and a γ/4 plate was attached to the side opposite to the side of the polarizer provided with an antireflection film, which was bonded to Attached to a glass plate of an organic EL display device so that the antireflection film is arranged on the outermost surface. A display device of this construction provides a relatively high visibility, while surface reflections and reflections from within the crystal are suppressed.

<Example B>

(Synthesis of perfluoroolefin copolymer (1))

Perfluoroolefin Copolymer(1)

(50:50 means molar ratio)

In a stainless steel autoclave with a volume of 100ml equipped with a stirrer, pour 40ml of ethyl acetate, 14.7g of hydroxyethyl vinyl ether and 0.55g of dilauroyl peroxide, and evacuate the inside of the system with nitrogen replacement. Then 25 g of hexafluoropropylene was added to the autoclave, which was then heated to 65°C. The autoclave showed a pressure of 0.53 MPa (5.4 kg/cm ² ) when the internal temperature reached 65°C. The reaction was continued for 8 hours while maintaining the temperature, and then the heating was stopped when the pressure reached 0.31 MPa (3.2 kg/cm ² ), and the system was allowed to stand to cool. When the internal temperature dropped to room temperature, unreacted monomers were vented and the reaction solution was taken out by opening the autoclave. The obtained reaction liquid was poured into a large excess of hexane, and the solvent was decanted to obtain a precipitated polymer. The polymer was then dissolved in a small amount of ethyl acetate and reprecipitated 2 times from hexane to completely remove residual monomers. 28 g of polymer were obtained after drying. Thereafter, 10 g of the polymer was dissolved in 100 ml of N,N-dimethylformamide, and then 11.4 g of acryloyl chloride were added dropwise under cooling with ice and the mixture was stirred at room temperature for 10 hours. Ethyl acetate was added to the reaction solution, washed with water and the organic layer was extracted and concentrated. The obtained polymer was reprecipitated from hexane to obtain 19 g of a perfluoroolefin copolymer (1). The obtained polymer had a refractive index of 1.421.

(Preparation of organosilane sol liquid)

In a reactor equipped with a stirrer and a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co. ) and 3 parts of ethyl diisopropoxyaluminum acetoacetate were mixed, and 30 parts of ion-exchanged water were added. The mixture was reacted at 60° C. for 4 hours, and cooled to room temperature to obtain an organosilane sol liquid. The weight average molecular weight was shown to be 1,600, and among the oligomer component and the larger component, the component having a molecular weight in the range of 1,000 to 20,000 accounted for 100%. Furthermore, gas chromatographic analysis revealed that no acryloxypropyltrimethoxysilane used as a raw material remained at all.

(Preparation of Coating Liquid A for Light Scattering Layer)

50 g of a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (PET-30, manufactured by Nippon Kayaku Co.) were diluted with 38.5 g of toluene. 2 g of a polymerization initiator (Irgacure 184, manufactured by Ciba Specialty Chemicals Co.) was also added and mixed under stirring. A film obtained by coating and ultraviolet curing of this solution exhibited a refractive index of 1.51.

To this solution, crosslinked polystyrene particles (refractive index 1.61, SX-350, manufactured by Soken Chemical & Engineering Co.) having an average particle diameter of 3.5 μm by dispersing in a Polytron disperser at 10,000 rpm for 20 minutes were added 1.7 g of 30% toluene dispersion obtained, and 13.3 g of 30% toluene dispersion of crosslinked acryl-styrene particles (refractive index 1.55, manufactured by Soken Chemical & Engineering Co.) with an average particle diameter of 3.5 μm ; Finally, 0.75 g of fluorinated surface modifier (FP-13), and 10 g of silane coupling agent (KBM-5103, manufactured by Shin-Etsu Chemical Co.) were added to obtain a mixed liquid (final liquid).

The mixed solution was filtered through a polypropylene filter with a pore diameter of 30 μm to prepare a coating solution A for the light scattering layer.

(Preparation of Coating Liquid B for Light Scattering Layer)

285 g of an industrial ultraviolet-curable hard coating solution containing zirconia (Desolite Z7404, manufactured by JSR Corp., solid content: about 61%, _ZrO content in solid: about 70%, polymerization initiator containing a polymerizable monomer agent) and 85 g of a mixture of pentaerythritol pentaacrylate and hexaacrylate (DPHA, manufactured by Nippon Kayaku Co.) were mixed, and diluted with 60 g of methyl isobutyl ketone and 17 g of methyl ethyl ketone. Also, 28 g of a silane coupling agent (KBM-5103, manufactured by Shin-Etsu Chemical Co.) was mixed under stirring. A film obtained by coating and ultraviolet curing of this solution exhibited a refractive index of 1.61.

Under stirring, in this solution, add 35g by using Polytron disperser under 10,000rpm and disperse 20 minutes and be the strongly cross-linked PMMA particle (refractive index: 1.49, MXS-300, by Soken Chemical & Engineering Co.) was obtained as a 30% methyl isobutyl ketone dispersion, and then 90 g of silica particles (refractive Ratio: 1.46, Seahoster KE-P150, manufactured by Nippon Shokubai Co.) A dispersion obtained as a 30% methyl ethyl ketone dispersion, and finally 0.12 g of a fluorinated surface modifier (P-12) was added under stirring , to obtain a mixed liquid (final liquid).

The mixed solution was filtered through a polypropylene filter with a pore diameter of 30 μm to obtain a coating solution B for a light scattering layer.

(Preparation of hard coat coating solution)

Viscote290 (by Osaka Organic 300 parts by weight

Chemical Industry Ltd.)

Viscote 190 (by Osaka Organic Chemical 300 parts by weight

Industry Ltd.)

Methyl ethyl ketone 360 parts by weight

Cyclohexanone 40 parts by weight

Irgacure 907 (manufactured by Nippon Ciba-Geigy Ltd.) 18 parts by weight

The mixture of the above components was stirred and filtered through a polypropylene filter with a pore size of 0.4 µm.

(Preparation of Coating Liquid for Antistatic Layer)

In 100 g of industrial ATO-dispersed hard coat agent (manufactured by Nippon Pelnox Ltd., solid: 45%, trade name: Peltron C-4456-S7), 30 g of cyclohexanone, 10 g of methyl ethyl ketone and 1.5 g of a silane coupling agent 3-acryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., trade name: KBM-5103), and the mixture was stirred, and a polypropylene with a pore diameter of 10 μm Filter through a filter to obtain a coating solution for an antistatic layer.

(Preparation of conductive hard coat coating solution)

In industrial zirconia ultrafine particle dispersion hard coat agent (manufactured by JSR Corp, solid: 50%, refractive index in hardened state: 1.69, trade name: Z-7401), disperse conductive particles ( Spherical powder of benzoguanamine-melamine-formaldehyde condensate plated with gold and nickel, manufactured by Nippon Chemical Industrial Co., trade name: Brite 20GNR4.6-EH), and the dispersion was coated with polypropylene having a pore diameter of 10 μm. Filtration was performed with a filter to obtain a coating solution for a conductive hard coat layer.

(Preparation of Titanium Dioxide Dispersion)

MPT-129C (manufactured by Ishihara Sangyo Co., 257.1g

TIO ₂ : Co ₃ O ₄ : Al ₂ O ₃ : ZrO ₂ =90.5:3.0:4.0:0.5,

by weight)

The following dispersant 38.6g

Cyclohexanone 704.3g

The mixture of the above components was dispersed with a refiner to a weight average diameter of 70 nm. Dispersant:

(Preparation of Coating Liquid for Middle Refractive Index Layer)

The aforementioned titanium dioxide dispersion 88.9g

DPHA (manufactured by Nippon Kayaku Co.) 58.4g

Irgacure 907 (manufactured by Chiba Specialty Chemicals Co.) 3.1g

Kayacure DETX (manufactured by Nippon Kayaku Co.) 1.1g

Methyl ethyl ketone 482.4g

Cyclohexanone 1869.8g

The mixture of the above components was stirred and filtered through a polypropylene filter with a pore size of 0.4 µm.

(Preparation of Coating Liquid for High Refractive Index Layer)

The aforementioned titanium dioxide dispersion 586.8g

DPHA (manufactured by Nippon Kayaku Co.) 47.9g

Irgacure907 (manufactured by Chiba Specialty Chemicals Co.) 4.0 g

KayacureDETX (manufactured by Nippon Kayaku Co.) 1.3g

Methyl ethyl ketone 455.8g

Cyclohexanone 1427.8g

The mixture of the above components was stirred and filtered through a polypropylene filter with a pore size of 0.4 µm.

(Preparation of Hollow Silica Dispersion)

In 500 parts of hollow silica particle sol (isopropanol silica sol CS60-IPA, manufactured by Catalysts & Chemicals Ind.Co., average particle diameter: 60nm, shell thickness: 10nm, silica concentration: 20%, di Refractive index of silica particles: 1.31), 30 parts of silane coupling agent 3-acryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., trade name: KBM-5103) and 1.5 parts diisopropoxyaluminum ethyl acetate, and then add 9 parts of ion-exchanged water. After reacting at 60°C for 8 hours, the mixture was cooled to room temperature, and 1.8 parts of acetylacetone was added to obtain a hollow silica dispersion. The hollow silica dispersion obtained exhibited a solids concentration of 18% by weight and a refractive index of 1.31 after evaporation of the solvent.

(Preparation of Coating Solution A for Low Refractive Index Layer)

DPHA (mixture of 5-functional and 6-functional acrylates) 1.4g

Perfluoroolefin copolymer (1) (containing acrylate in the side chain) 5.6g

Hollow silica dispersion 20.0g

Polysiloxane compound 0.7g

(RMS-033, manufactured by Chisso Corp.)

Irgacure 907 0.2g

Organic silane sol liquid 6.2g

Methyl ethyl ketone 315.9g

The film obtained by coating, drying and curing the above coating liquid showed a refractive index of 1.43.

(Preparation of Coating Solution B for Low Refractive Index Layer)

DPHA (mixture of 5- and 6-functional acrylates) 3.6g

Hollow silica dispersion 20.0g

RMS-033 0.7g

Irgacure 907 0.2g

Organic silane sol liquid 8.0g

Methyl ethyl ketone 276.0g

The film obtained by coating, drying and curing the above coating liquid showed a refractive index of 1.41.

(Preparation of Coating Solution C for Low Refractive Index Layer)

Pentaerythritol triacrylate 90.0g

Hollow silica dispersion 20.0g

Octafluoropentyl methacrylate 10.0g

The film obtained by coating, drying and curing the above coating liquid showed a refractive index of 1.48.

[Example B-1]

(1) Coating of light scattering layer

A roll-shaped triacetylcellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co., Ltd.) having a thickness of 80 μm was unrolled using a gravure pattern having a line count of 180 lines/inch and a depth of 40 μm and a diameter of 50mm micro-gravure roll and doctor blade, coating the coating solution A of the light scattering layer under the condition that the gravure roll rotation speed is 30rpm and the transport speed is 30m/min, then dry at 60°C for 150 seconds, and use 160W/cm An air-cooled metal halide lamp (manufactured by Eyegraphics Co.) was irradiated with ultraviolet light with an irradiation intensity of 100 mW/cm ² and an irradiation amount of 60 mJ/cm ² in an atmosphere with an oxygen concentration of 0.005% by volume under nitrogen flushing, and the The coating was hardened, whereby a light-scattering layer having a refractive index of 1.51 and a thickness of 6 μm was obtained, and then the film was rolled up again.

(2) Coating of low refractive index layer

The triacetyl cellulose film coated with the light-scattering layer was developed again, using a micro-gravure roll and a doctor blade with a gravure pattern of 180 lines/inch and a depth of 40 μm and a diameter of 50 mm, at a rotation speed of the gravure roll of 30rpm and conveying speed are the coating solution A of coating low-refractive index layer under the condition of 15m/min, dry 150 seconds at 90 ℃ then, and use the air-cooled metal halide lamp of 240W/cm ² (by Eyegraphics Co. Manufacture) The coating was hardened by irradiating ultraviolet light with an irradiation intensity of 400 mW/cm ² and an irradiation amount of 900 mJ/cm ² in an atmosphere having an oxygen concentration of 0.1% by volume under nitrogen flushing, thereby obtaining a refractive index of 1.43 and A low refractive index layer with a thickness of 100 nm was then rolled up.

(3) Saponification of anti-reflective film

After film formation, the aforementioned thin film was subjected to the following treatments.

Prepare a 1.5 mol/L sodium hydroxide aqueous solution and keep it at 55°C. A 0.005 mol/L dilute sulfuric acid aqueous solution was also prepared and kept at 35°C. The prepared antireflection film was soaked in sodium hydroxide aqueous solution for 2 minutes.

Then soak in water and rinse off the aqueous sodium hydroxide solution well. Then, soak in dilute sulfuric acid solution for 1 minute, and soak in water to fully rinse off the dilute sulfuric acid solution. Finally, the samples were fully dried at 120 °C.

In this way, a saponified antireflection film, which is designated as Example B-1, Sample 1, was produced.

(Evaluation of anti-reflection film)

The following items were evaluated for the obtained films. The results are shown in Table 1.

(1) Average reflectance

The spectral reflectance at an incident angle of 5° was measured with a spectrophotometer (manufactured by Jasco Corp.) in the wavelength range of 380-780 nm. The results use the average reflectance of an integrating sphere over the wavelength range of 450-650 nm.

(2) Evaluation of scratch resistance of steel wool

Use a friction tester to carry out the friction test under the following conditions:

Environmental conditions for evaluation: 25°C, 80%RH;

Friction material: Steel wool (grade 0000, manufactured by Nippon Steel Wool Co.) was wound around the friction end (1 cm × 1 cm) of the analyzer to be in contact with the sample and fixed with a belt;

Moving distance (one way): 13cm, friction speed: 13cm/sec, load: 0.049MPa (500g/cm ² ), front contact area: 1cm×1cm, friction times: 10 reciprocating cycles.

After rubbing, apply oily black ink on the back of the sample, observe the scratches on the rubbed part with naked eyes under reflected light and evaluate according to the following criteria:

AA: No scratches were observed even when observed very carefully;

A: Weak scratches can be observed very carefully;

AB: Weak scratches can be observed;

B: A moderate level of scratches can be observed;

BC-C: Scratches can be easily observed.

(3) Evaluation of the friction resistance of the cotton pad

Fix the cotton pad on the friction end of the friction tester, fix the sample on the smooth plate with the upper and lower parts of the clamp, soak the sample and the cotton pad in water at 25°C, and put 500g of The load is subjected to different times of friction cycles, and the friction test is carried out. The friction conditions are as follows:

Friction distance (one way): 1cm, friction speed: about 2 cycles/second.

The samples after rubbing were observed, and the rubbing resistance was evaluated by the number of cycles causing film peeling as follows:

C: The film is peeled off within 0-10 reciprocating cycles;

BC: The film is peeled off within 10-30 reciprocating cycles;

B: The film is peeled off within 30-50 reciprocating cycles;

AB: The film is peeled off within 50-100 reciprocating cycles;

A: The film is peeled off within 100-150 reciprocating cycles;

AA: The film does not peel off within 150 reciprocating cycles.

(4) Evaluation of rubber friction resistance

Fix the rubber (MONO, manufactured by Tombow Pencil Co.) on the friction end of the friction tester, fix the sample on the smooth plate with the upper and lower parts of the clamp, and place it on the rubber (plane pressure: 0.049MPa (500g/ cm ² ) with a load of 250g for different times of friction cycles, to carry out the friction test. The friction conditions are as follows:

Friction distance (one way): 1cm, friction speed: about 1 reciprocating cycle/second.

The sample after rubbing was observed, and the rubbing resistance was evaluated by the number of reciprocating cycles causing film peeling as follows:

C: The film is peeled off within 0-10 reciprocating cycles;

BC: The film is peeled off within 10-30 reciprocating cycles;

B: The film is peeled off within 30-50 reciprocating cycles;

AB: The film is peeled off within 50-100 reciprocating cycles;

A: The film is peeled off within 100-150 reciprocating cycles;

AA: The film does not peel off within 200 reciprocating cycles.

(5) Evaluation of stain resistance

A circle with a diameter of 5 mm was drawn on the surface of the antireflection film with a ZEBRA Macky marker (black), and the stain resistance was evaluated by the number of times the stain could not be wiped off with tissue paper after 3 seconds. Stain resistance was evaluated as follows:

C: not wiped off within 0-2 times of painting;

B: not wiped off within 3-10 times of painting;

A: It is not wiped off within 11-15 times of painting;

AA: Wipe off after 15 draws.

[Example B-1, samples 2-4, 5, 6 (present invention) and samples 5, 8, 9 (comparative examples)]

Samples were prepared and evaluated in the same manner as in Example B-1, Sample 1, except that the coating liquid for the light scattering layer in Example B-1, Sample 1 was replaced with the coating liquid (B) for the light scattering layer, or The coating solution for the low refractive index layer was replaced with the coating solution (B) or (C) for the low refractive index layer shown in Table 7, or the atmospheric oxygen concentration at the time of curing after evaporation of the solvent was changed as shown in Table 8. The results are shown in Table 7.

The light-scattering layer in the case of using the coating liquid B for the light-scattering layer had a thickness of 3.4 μm after drying. Instead, only in Sample 9, saponification was performed as in Example 1 after forming the light-scattering layer, and a low-refractive-index layer was formed thereafter.

Table 7 Sample of Example B-1 light scattering layer low refractive index layer Oxygen concentration in curing atmosphere (volume %) Reflectivity Scratch resistance Stain resistance coating coating (volume%) (%) steel wool cotton pad eraser Sample 1 (the present invention) A A 0.05 2.0 AAA AAA AAA AAA Sample 2 (the present invention) A A 0.1 2.0 AAA AAA AAA AAA Sample 3 (the present invention) A A 2.0 2.0 A AAA A AAA Sample 4 (the present invention) A A 10.0 2.0 B AAA B AAA Sample 5 (the present invention) A A 20.5 2.0 C C C AAA Sample 6 (the present invention) A B 0.05 1.9 AAA AAA AAA A Sample 7 (the present invention) B A 0.05 1.5 A A A AAA Sample 8 (comparative example) B A 20.5 1.5 C C C AAA Sample 9 (comparative example) A C 20.5 1.5 C C C C

The results in Table 7 illustrate the following

In the antireflection film of the present invention, when the hardenable component having a polymerizable functional group undergoes radical polymerization by ultraviolet irradiation during curing of the low-refractive index layer, an atmosphere having an oxygen concentration of 15% by volume or less suppresses oxygen Inhibition of polymerization, thereby providing a low refractive index layer with satisfactory scratch resistance as represented by rub tests of steel wool, cotton bedding, and rubber.

Moreover, the refractive index of the low-refractive-index layer can be kept very low by using inorganic particles having an average particle diameter in the range of 30-150% of the thickness of the low-refractive-index layer and having a hollow structure with a refractive index of 1.17-1.40.

Therefore, the present invention can provide an antireflection film having excellent antireflection characteristics and high scratch resistance.

In Example B-1 and Sample 1-7, the dilution solvent in the coating solution A of the light scattering layer was changed from toluene to a combination of toluene/cyclohexanone=85/15 or toluene/cyclohexanone=70/30 material, thereby improving the interfacial adhesion of the transparent substrate/light-scattering layer, and increasing the scratch resistance as the proportion of cyclohexanone increases.

[Example B-2]

(1) Coating and saponification of hard coat/three-layer anti-reflection layer

On a triacetylcellulose film (TD-80UF, manufactured by Fuji PhotoFilm Co.) having a thickness of 80 μm, the aforementioned hard coat coating solution was coated, and hardened by solvent evaporation and ultraviolet irradiation as described in Table 8 to obtain a hard coat layer (HC), on which the middle refractive index layer (Mn), high refractive index layer (Mn) and high refractive index layer (Hn) and low refractive index layer (Ln). A hard coat/three-layer antireflection layer-loaded film was thus obtained, which was saponified as in Example B-1 to obtain Example B-2, Sample 1.

Table 8 layer system Drying air temperature (℃) UV radiation (mJ/cm ² ) _O2 concentration (volume%) Dry film thickness (nm) Refractive index HC MG 60 160 0.1 8000 1.51 mn MG 110 300 0.1 65 1.63 h MG 110 500 0.1 105 1.90 ln MG 90 900 0.05 84 1.44

MG represents the same microgravure coating system as in Example B-1.

Furthermore, Example B-2, Sample 2-4 (the present invention), and 5 (Comparative Example) were prepared in the same manner as Example B-2, Sample 1, except that the atmospheric oxygen concentration was as follows when the low-refractive index layer was cured. Changes are shown in Table 9.

Table 9 Sample in Example B-2 low refractive index layer Oxygen concentration in curing atmosphere Reflectivity Scratch resistance Coating solution (volume%) (%) steel wool cotton pad eraser Sample 1 (the present invention) A 0.05 0.4 AAA AAA AAA Sample 2 (the present invention) A 0.1 0.4 AAA AAA AAA Sample 3 (the present invention) B 0.05 0.3 A AAA A Sample 4 (the present invention) B 0.1 0.3 A AAA A Sample 5 (comparative example) A 18.0 0.4 C C C

The results in Table 9 show that in the three-layer antireflection film, as in Example B-1, atmosphere suppression with an oxygen concentration of 15% by volume or less can obtain a low antireflection film with satisfactory scratch resistance. The refractive index layer, and the use of hollow structure inorganic particles with a refractive index of 1.17-1.40 can maintain the low refractive index of the low refractive index layer, thereby obtaining an antireflection film with low reflectivity.

[Example B-3]

(1) Preparation of antistatic hard coating film

The prepared coating solution for the antistatic layer was applied to a triacetyl cellulose film (manufactured by Fuji Photo Film Co., trade name: TD-80U, thickness: 80 μm), dried at 70° C. for 1 minute, and subjected to Hardened by ultraviolet irradiation (100 mJ/cm ² ), an antistatic film with a thickness of about 0.2 μm was obtained. Then, on the antistatic layer, the conductive hard coat coating solution obtained was coated and dried at 70° C. for 1 minute, and hardened by ultraviolet irradiation (120 mJ/cm 2 ) under nitrogen flushing to obtain a film having a thickness of about 5 μm. Antistatic hard coat film. Properties are shown in Table 10.

Table 10 Transmittance surface resistance 92% 5×10 ⁷ -5×10 ⁸

On this antistatic hard coat film, a low-refractive index layer is then formed in the same manner as in Example B-1 to obtain an antistatic antistatic film having the aforementioned antistatic properties, a reflectivity of 2.2%, and excellent scratch resistance and visibility. reflective film.

[Example B-4]

Soak the PVA film in an aqueous solution containing 2.0g/l iodine and 4.0g/l potassium iodide for 240 seconds at 25°C, then soak it in an aqueous solution containing 10g/l boric acid for 60 seconds at 25°C, and add it to JP - In a tenter of the shape described in Fig. 2 of A 2002-86554, and extended to 5.3 times, whereby the tenter is bent relative to the direction of extension shown in Fig. 2 of the aforementioned patent document, and the width is then kept constant . After drying in an environment of 80° C., the film was removed from the tenter. The left and right tenter clips have less than a 0.05% difference in transport speed, and the centerline of the incoming film and the centerline of the film advancing to the next step form an angle of 46°. The conditions |L1-L2| are kept at 0.7m and W at 0.7m such that |L1-L2|=W. The approximate extension direction Ax-Cx at the tenter exit is inclined at 45° with respect to the center line 22 of the film advancing to the next step. At the exit of the tenter frame, no shrinkage or film deformation was observed.

It was then adhered to a saponified Fujitac film (cellulose triacetate, retardation: 3.0 nm, manufactured by Fuji Photo Film Co.) using a 3% aqueous solution of PVA (PVA-117H, manufactured by Kuraray Co.) as a binder. manufacturing) and dried at 80°C to obtain a polarizing plate with an effective width of 650 mm. The obtained polarizing plate had an absorption axis inclined at 45° with respect to the longitudinal direction. The polarizer has a transmittance of 43.7% and a degree of polarization of 99.97% at 550 nm. This was cut into a size of 310×233 mm as shown in FIG. 2 , thereby providing a polarizing plate whose absorption axis was inclined at 45° with respect to the faces, in which the area yield was 91.5%.

Then the films of Example 1, Sample 1 or Example 2, Sample 1 (both subjected to the saponification process) were bonded to the polarizer to obtain an anti-glare and anti-reflection polarizer. A liquid crystal display device prepared using the polarizer having an anti-reflection layer on the outermost layer exhibits excellent contrast due to no reflection of external light; and excellent visibility due to inconspicuous reflected light due to its anti-glare performance. Specifically, the film of Example B-1, Sample 1 provided an excellent display device excellent in contrast due to its low reflectance.

[Example B-5]

A triacetyl cellulose film (TD-80U, manufactured by FujiPhoto Film Co.) with a thickness of 80 μm soaked in 1.5 mol/L NaOH aqueous solution at 55° C. for 2 minutes, then neutralized and rinsed with water, and Example B -1, sample 1 or embodiment B-2, the saponified triacetyl cellulose film of sample 1, they are adhered on the both sides of the known polarizer made by iodine adsorption and polyvinyl alcohol extension, obtained a polarizer. Using the polarizer thus prepared, the antireflection film constitutes a transmissive TN liquid crystal display device for a notebook personal computer (Polarized light separation film D-BEF with a polarization selective layer between the back light and the liquid crystal cell, developed by Sumitomo- 3M Co.), instead of the polarizing plate on the observation side, thereby obtaining a display device having a very high display quality while the reflection of the external view is very small.

[Example B-6]

A viewing angle widening film (wide-view film SA 12B manufactured by FujiPhoto Film Co.) with an optical compensation layer, wherein the disc of the disc-shaped structural unit is inclined towards the surface of the transparent substrate, and the disc-shaped surface of the disc-shaped structural unit and The angle between the surfaces of the transparent substrate varies with the depth of the optically anisotropic layer, on the side of the liquid crystal cell, this film, used as a protective film for the polarizer on the viewing side of the transmissive TN liquid crystal cell, on which the example The film of B-1, Sample 1 or Example B-1, Sample 7, was on the liquid crystal cell side, and was used as a protective film of a polarizing plate on the back light side. As a result, a liquid crystal display device is obtained which exhibits high contrast in a bright room, exhibits very wide viewing angles in the upper, lower, and horizontal directions, and exhibits extremely excellent visibility and high display quality. And relative to the exit angle of 0°, the film of embodiment B-1 and sample 7 (using the anti-glare hard coating solution B) shows a light scattering intensity ratio of 0.06% at an exit angle of 30°, and this light scattering performance It is particularly advantageous to increase the viewing angle in the downward direction and to improve the yellowish hue in the horizontal viewing direction, thereby providing a very satisfactory liquid crystal display device. On the contrary, with respect to the exit angle of 0°, the film of Example 2, Sample 1 (clear three-layer anti-reflection film) shows almost 0% light scattering intensity ratio at the exit angle of 30°, and shows no increase in downward viewing angle at all and enhance the effect of yellowish tones.

[Example B-7]

Prepare a polarizing plate with an antireflection film with the film of Example B-2, sample 1 and the λ/4 plate attached to the opposite face of the antireflection film, and adhere to the uppermost surface of the display surface side of the organic EL display device The outer surface. As a result, a display with extremely high visibility is obtained due to reduced surface reflections and reflections from inside the surface glass.

<Example C>

<Spectral characteristics of ultraviolet absorbing monomers>

Table 11 shows the spectral characteristics of the ultraviolet absorbing monomers used in the following Examples and Comparative Examples.

Table 11 compound ε(380nm) ε(380nm)/ε(400nm) Contrast UV-1 750 50 or higher Contrast UV-1 3,300 16 UVM-1 6,700 50 or higher UVM-2 7,800 50 or higher UVM-5 10,500 40 UVM-7 11,300 50 UVM-11 7,000 50 or higher UVM-20 8,500 15

In Table 11, ε(380nm) represents the molar absorptivity at 380nm, and ε(380nm)/ε(400nm) represents the ratio of the molar absorptivity at 380nm to the molar absorptivity at 400nm.

Spectral absorbance was measured in dichloromethane solvent.

The structures of comparative compound UV-1 and comparative compound W-2 are shown below.

Comparison with UV-1 Comparison with UV-2

[Example C-1]

<Preparation of Substrate (Example C1-1)>

(Preparation of Cellulose Acylate Solution (A-1))

The mixture of the following components was stirred and dissolved to obtain a cellulose acylate solution (A-1).

(Components of Cellulose Acylate Solution (A-1))

Cellulose triacetate with a substitution degree of 2.85 (6-position substitution degree: 0.90) 89.3 parts by weight

Plasticizer (polyol ester example compound 8) 18.2 parts by weight

The following ultraviolet absorber: UV-1 5.7 parts by weight

Dichloromethane 300 parts by weight

Methanol 54.0 parts by weight

1-butanol 11.0 parts by weight

Ultraviolet absorber: UV-1 is a copolymer of the aforementioned ultraviolet absorbing monomer UVM-1 and MMA (weight average molecular weight: 12,000, ultraviolet absorbing monomer content: 55% by weight).

(Preparation of Coating Dope)

The cellulose acylate solution of 479 parts by weight was fully stirred, and left to stand at room temperature (25°C) for 3 hours, and the obtained gel-like solution was cooled at -70°C for 6 hours and heated and stirred at 50°C to obtain Totally dissolved coating dope.

The obtained coating dope was filtered at 50° C. with a filter paper (#63, manufactured by Toyo Filtering Paper Co.) with an absolute filtration precision of 0.01 mm, and then with a filter paper with an absolute filtration precision of 0.0025 mm (FH025, manufactured by Pall Inc.) to filter and remove air bubbles to obtain a coating dope.

(solution casting process)

After the aforementioned preparation of the cellulose acylate solution, the coating dope thus obtained was cast with a belt caster used in the process of preparing a cellulose acylate film from the cellulose acylate solution.

A metal base (casting belt) of stainless steel having a width of 2 m and a length of 56 m (area 112 m ² ) was used. The metal substrate had an arithmetic average roughness (Ra) of 0.006 μm, a maximum height (Ry) of 0.06 μm, and a ten-point average roughness (Rz) of 0.009 μm. Arithmetic mean roughness (Ra), maximum height (Ry) and ten-point mean roughness (Rz) were measured in accordance with JIS B0601.

Immediately after casting, the casting coating dope was dried with an air velocity of 0.5 m/sec or less for 1 second, and then dried with an air velocity of 15 m/sec. The temperature of the drying air was 50°C.

The residual solvent content of the film peeled from the casting tape was 230% by weight, and the temperature was -6°C. The average drying rate from casting to peeling was 744%/min, and the gelling temperature of the coating dope at the time of peeling was about 10°C.

The film was dried for 1 minute after the surface temperature of the film on the metal substrate reached 40°C, and then peeled off, and the temperature of the drying air was changed to 120°C. In this state, the temperature distribution of the film in the transverse direction is 5°C or less, the average velocity of dry air is 5m/sec, the heat transfer coefficient is 25kcal/m ² ·Hr·°C on average, and the film has a temperature of 5% in the transverse direction. The distribution of these values within . In the drying zone, the part of the film carried by the tenter needles is blocked by the air to avoid the drying hot air.

A process of stretching the cellulose acylate film is then performed. In the state of a film with a residual solvent amount of 15% by weight, the film was stretched transversely at 130°C at a stretching coefficient of 25% via a tenter, then kept at this stretched width at 50°C for 30 seconds, and then removed from the stretcher. Release on the frame clips and wind into a roll. The solvent evaporation from peeling to rolling up corresponds to 97% by weight of the solvent originally used. The dried film was then dried with dry air at 145° C. in the drying step under roller transport, and then subjected to temperature and humidity adjustment and rolled up at a residual solvent amount of 0.35% by weight and a moisture content of 0.8% by weight, thereby obtaining fibers A monocylate film (CA1-1) (length 3500 m, width 1300 mm, thickness 80 µm) was used as the transparent substrate of Example C1-1.

The cellulose acylate film (CA1-1) thus produced had a thickness fluctuation of ±2.4%, and a curl value in the transverse direction of -4.5/m.

[Comparative Examples C1-1 to C1-4]

(comparative example C1-1)

A cellulose acylate film (CAR1-1) having a thickness of 80 μm was prepared in the same manner as in Example C1-1, except that dry air with an average air velocity of 24 m/s and a temperature of 60° C. was used during film casting and The casting conditions were changed to obtain the physical properties shown in Table 12.

(comparative example C1-2)

As shown in Table 12, a cellulose acylate film (CAR1-2) having a thickness of 79 μm was prepared in the same manner as in Example C1-1 except that there was no plasticizer (polyol ester exemplified compound 8) and cellulose acetate element increased by a corresponding amount.

(comparative example C1-3)

As shown in Table 12, a cellulose acylate film (CAR1-3) having a thickness of 80 μm was prepared in the same manner as in Example C1-1 except that there was no ultraviolet absorber (UV-1) and cellulose acetate was increased corresponding amount.

(comparative example C1-4)

As shown in Table 12, a cellulose acylate film (CAR1-4) having a thickness of 80 μm was prepared in the same manner as in Example C1-1 except that dipropylene glycol dibenzoate was omitted and triphenyl phosphate was increased. corresponding amount.

Table 12 film number Thickness μm Thickness variation range (%) curly Raμm Rzμm Ra/Rz Smμm Ryμm Haze% Tear strength (g) optical defect Moisture permeability (g/m ² /24h) Exudation performance (%) Example C1-1 CA1-1 80 ±2.4 -4.5 0.006 0.018 0.333 0.150 0.072 0.25 12 0.4 175 0.9 Comparative Example C1-1 CAR1-1 80 ±5.5 -7.3 Unable to measure due to lack of planarity 8 1.1 197 1.2 Comparative Example C1-2 CAR1-2 79 ±3.8 -9.3 0.008 0.030 0.267 0.180 0.180 0.31 15 1.4 285 2.3 Comparative Example C1-3 CAR1-3 80 ±3.6 -6.6 0.008 0.028 0.286 0.123 0.123 0.30 13 1.5 295 2.4 Comparative Example C1-4 CAR1-4 79 ±3.2 -4.3 0.007 0.033 0.212 0.235 0.147 0.30 11 1.1 305 2.6

(surface irregularities of the film)

Table 12 shows the results of measuring the surface irregularities on the tape side surface of the cellulose acylate film samples CA1-1 and CAR1-1 to CAR1-4. Table 12 also shows the evaluation results of the following optical characteristics and mechanical properties.

(Optical properties of thin films)

(1) Haze

Haze was measured with a haze meter (Model 1001DP, manufactured by Nippon Denshoku Kogyo Co.). Measurements were made at 5 points on each film sample and the average value calculated.

(evaluation of mechanical properties)

(2) curly

The curl value was determined according to the test method defined by the American National Standards Institute (ANSI/ASCPH 1.29-1985, Method-A). The polymer film was cut into a size of 35 mm in width and 2 mm in length, and fixed on a curling plate. The curl value after humidity conditioning for 1 hour in an environment of 25° C. and 65% RH was read. Similarly, a polymer film was cut into a size of 2 mm in width and 35 mm in length and fixed on a curling plate. The curl value after humidity conditioning for 1 hour in an environment of 25° C. and 65% RH was read. The measurement was carried out in the transverse direction and the longitudinal direction, and the larger value was taken as the curl value. The curl value is represented by the reciprocal of the radius of curvature (m).

(3) Tear strength

The film was cut into a size of 65mm wide and 50mm long to make a sample, and then it was subjected to humidity conditioning in a room with a temperature of 30°C and a relative humidity of 85%, and a light load tear strength tester manufactured by Tokyo Seiki Mfg.Co. in accordance with ISO6383 /2-1983 Determination of the load (g) required for tearing.

(other film properties)

(4) Optical defects

Two polarizers were placed in crossed Nicols position, and a sample with a width of 1300 mm and a length of 5 m was placed between them, and brightness defects were counted under naked eye observation. The number of bright spots with a size of 100 μm or larger is counted and expressed in number per meter.

(5) Moisture permeability

Measured according to the method defined in JIS Z0208 (measured at 25°C, 90%RH).

(6) Exudation performance

Film samples were cut into a size of 10×10 cm, and weighed after standing at 23°C and 55% RH for 1 day, and at 80°C and 90% RH for 2 weeks. After the sample was left to stand for 1 day at 23° C. and 55% RH, the weight was measured, and the retention performance was calculated by the following formula:

Exudation property={(sample weight before treatment-sample weight after treatment)/sample weight before treatment}×100(%)

<Preparation of anti-reflection film>

[Example Cla]

(Preparation of anti-reflection film (KH-01))

^* Preparation of the coating solution for the light-diffusing layer

50 parts by weight of an ultraviolet curable resin (Kayarad PET-30, refractive index 1.51, manufactured by Nippon Kayaku Co.) as a translucent resin constituting the light-diffusing layer, 2 parts by weight of a curing initiator (Irgacure 184, manufactured by Ciba -Geigy Inc.), 5 parts by weight of acryloyl-styrene beads (manufactured by Soken Chemical and Engineering Co., particle diameter: 3.5 μm, refractive index: 1.55) as the first translucent particles, 5.2 parts by weight of benzene Vinyl beads (manufactured by Soken Chemical and Engineering Co., particle diameter: 3.5 μm, refractive index: 1.60) as second translucent particles, 10 parts by weight of silane coupling agent KBM-5103 (manufactured by Shin-Etsu Chemical Co. ) and 0.03 parts by weight of the following fluorinated polymer (f1) were mixed with 50 parts by weight of toluene to obtain a coating liquid.

^* Coating of light diffusion layer

The aforementioned cellulose acylate film CA1-1 was unwound from a roll and coated with a coating liquid for a light-diffusing layer to obtain a dry film thickness of 6.0 μm, and after evaporation of the solvent, was cooled with a 160 W/cm metal halide A lamp (manufactured by Eyegraphics Co.) was irradiated with ultraviolet light at an illuminance of 400 mW/cm ² and an irradiation amount of 300 mJ/cm ² to harden the coating, thereby obtaining a film (K-01) with a light-diffusing layer.

Fluorinated polymers (f1)

Mw1.5×10 ⁴ (calculated by molar composition ratio)

(Preparation of Low Refractive Index Layer)

^* Preparation of Coating Liquid (LL-1) for Low Refractive Index Layer

The fluoropolymer (FP-1) of the following structure was dissolved in methyl ethyl ketone at a concentration of 3% by weight, and was added in an amount of 30% by weight of the hollow silica solid relative to the solid of the fluoropolymer Hollow silica (CS-60-IPA, average particle diameter: 60 nm, shell layer thickness: 10 nm, refractive index: 1.31, 20% by weight of isopropanol dispersion, manufactured by Catalysts & Chemicals Ind. Co.), relatively solid Polysiloxane resin X-22-164C (manufactured by Shin-Etsu Chemical Co.) containing a terminal methacrylate group in an amount of 3% by weight, and a photoradical generator in an amount of 5% by weight relative to the solid Irgacure 907 (manufactured by Ciba-Geigy Inc.), a coating liquid LL-1 for obtaining a low refractive index layer. Fluoropolymer (FP-1)

Mw5×10 ⁴ (calculated by molar composition ratio)

^* Coating of low refractive index layer

The coating liquid LL-1 for the low-refractive index layer was applied onto the light-diffusing layer (HKF-01) with a gravure coater. After drying at 80° C. for 2 minutes, an air-cooled metal halide lamp (manufactured by Eyegraphics Co.) of 160 W/cm was used in an atmosphere having an oxygen concentration of 1.0% by volume or less under nitrogen flushing at an irradiation intensity of 300 mW/cm ² and It was irradiated with ultraviolet light at an irradiation amount of 250 mJ/cm ² to obtain a low-refractive index layer (refractive index: 1.43, film thickness: 86 nm). In this way, the antireflection film (HK-01) of the present invention was produced.

[Example C1b]

(Preparation of anti-reflection film (HK-02))

A substrate and a light-diffusing layer were prepared in the same manner as in Example C1a. More specifically, a light-diffusing layer (HKF-01) was coated on the cellulose acylate film CA1-1 of Example C1.

(Preparation of Low Refractive Index Layer)

^* Preparation of Coating Liquid (LL-2) for Low Refractive Index Layer

100 g of trifluoropropyltrimethoxysilane, 200 g of tridecafluorooctyltrimethoxysilane, 1700 g of tetraethoxysilane, 200 g of isopropanol, and 6 g of aluminum acetylacetonate were poured into a beaker and stirred. Then 500 g of a 0.25 mol/l acetic acid aqueous solution was added dropwise, and after the dropwise addition was completed, the mixture was stirred at room temperature for 3 hours. Then 600 g of diacetone alcohol were added. Then 600 g of the same hollow silica (CS60-IPA, 20% by weight) as in the coating liquid LL-1 of the low refractive index layer was added, and the mixture was stirred and filtered through a polypropylene filter with a pore size of 1 μm to obtain a low Coating liquid (LL-2) for the refractive index layer.

^* Coating of low refractive index layer

For the coating liquid LL-2 of the low refractive index layer, immediately before coating, the volatile organic solvent therein was evaporated, and then 1% by weight of isoflurane was added based on the solids of the coating liquid (LL-2). Ketone diisocyanate, coated with an extrusion coater onto the triacetylcellulose film coated with the anti-glare hard coat described above. After drying at 80°C for 2 minutes and curing at 120°C for 20 minutes, an air-cooled metal halide lamp (manufactured by Eyegraphics Co.) of 240 W/cm was used under nitrogen flushing at an irradiation intensity of 400 mW/ ^cm2 and an irradiation amount of 200 mJ/ cm ² of ultraviolet light irradiates it to obtain a low-refractive-index layer with a thickness of 100 nm. An antireflective film (HK-02) was produced in this way.

[Example C1c]

(Preparation of anti-reflection film (HK-03))

A substrate and a light-diffusing layer were prepared in the same manner as in Example C1a. More specifically, a light-diffusing layer (HKF-01) was coated on the cellulose acylate film CA1-1 of Example C1.

(Preparation of Low Refractive Index Layer)

^* Preparation of Coating Liquid (LL-3) for Low Refractive Index Layer

The coating liquid LL-3 of the low refractive index layer was prepared in the same manner as the coating liquid LL-2 of the low refractive index layer, but, in the final step, 30 g of polysiloxane leveling agent (linear dimethyl silicone Oxane-EO block copolymer (trade name: L-9000 (CS100), manufactured by Nippon Unicar Co.).

^* Coating of low refractive index layer

The antireflection film HK-03 was prepared by the same steps of coating, drying, heating and ultraviolet irradiation as in the antireflection film HK-02, except that the coating liquid LL-3 of the low refractive index layer was used to replace the coating of the low refractive index layer. Cloth liquid LL-2.

[Comparative Example C1-5]-[Comparative Example C1-10]

Compared with the antireflection film (HK-01) of Example C1a, the following comparative samples with different configurations were prepared:

(1) The same sample as in Example C1a, except that the cellulose acylate substrate CAR1-1 was used (the film is designated by HFR1)

(2) The same sample as in Example C1a, except that cellulose acylate substrate CAR1-2 (HFR2) was used;

(3) The same sample as in Example C1a, except that cellulose acylate substrate CAR1-3 (HFR3) was used;

(4) The same sample as in Example C1a, except that cellulose acylate substrate CAR1-4 (HFR4) was used;

(5) A sample formed by preparing a coating liquid (LR-1) for the low refractive index layer by removing the hollow silica therein and adding a corresponding weight of fluoropolymer and coating the liquid in the same manner as in Example C1a (HFR5); and

(6) Preparation of low refraction by substituting the same amount of non-hollow (ordinary) silica particles (different particle size grade from MEK-ST, particle size: 45 μm, manufactured by Nissan Chemical Industries Ltd.) in which hollow silica The coating liquid (LR-2) of the rate layer was coated and the sample (HFR6) formed of this liquid was coated in the same manner as in Example C1a.

(Evaluation of anti-reflection film)

The obtained films were evaluated for the following items, and the results are shown in Table 13.

(1) Anti-reflection performance

The specular reflectance at an incident angle of 5° and an outgoing angle of -5° in the wavelength range of 450-650 nm was measured by a spectrophotometer V-550 (manufactured by Jasco Corp.) equipped with an adapter ARV-47, and calculated by Average reflectance to get specular reflectance. Smaller values are preferred.

(2) Anti-glare performance

An exposed fluorescent lamp (6500 cd/m ² ) without a louver was reflected on the prepared antireflection film, and the blurring level of the reflected image was evaluated by the following criteria:

AA: The outline of the fluorescent lamp is not recognized at all;

A: The outline of the fluorescent lamp can be recognized slightly;

B: Fluorescent lights are blurry but outlines can be recognized;

C: The fluorescent lamp is hardly blurred.

(3) Evaluation of adhesive performance

The anti-reflection film was subjected to humidity conditioning for 2 hours under the conditions of a temperature of 25° C. and a humidity of 60% RH. Then, on the surface of the antireflection film on the side of the light-diffusing layer, use a cutter to cut eleven notches in the longitudinal and transverse directions to form 100 squares, and then glue them with a polyester adhesive tape (No. The adhesion test (manufactured by Nitto Denko Co.) was repeated 3 times, and the degree of peeling was visually observed and evaluated in the following four levels:

AA: No peeling was observed in all 100 squares;

A: Peeling was observed in 2 or less of 100 squares;

B: Peeling was observed in 3-10 out of 100 squares;

C: Peeling was observed in more than 10 out of 100 squares.

(4) Evaluation of scratch resistance of steel wool

On the antireflective film before and after exposure, after moving #0000 steel wool for 10 reciprocating cycles with a load of 500 g/cm ² , scratches were visually observed and evaluated at the following three levels:

A: No scratches at all;

B: The scratches formed are not easy to see;

C: Scratches are conspicuous.

(5) Dustproof performance (dust deposition resistance)

The film to be measured was adhered to a glass plate, and then subjected to charge removal and rubbing with Toresee (manufactured by Toray Inc.) for 10 reciprocating cycles. Then spray fine foaming styrene powder as pseudo-dust on the whole film, then let the film stand vertically, and observe the way the pseudo-dust falls, and evaluate according to the following four levels:

AA: Pseudo-dust falls almost completely;

A: 80% or more of false dust falls;

B: 50% or more of false dust fall;

C: 50% or more of pseudo dust remained on the surface of the film.

(6) Tone uniformity

The specular reflectance at an incident angle of 5° and an outgoing angle of -5° in the wavelength range of 450-650 nm was measured by a spectrophotometer V-550 (manufactured by Jasco Corp.) equipped with an adapter ARV-47, and then used in The reflectance spectrum measured in the wavelength range of 450-650nm calculates the L ^* , a ^* and b ^* values of the CIE1976L ^* a ^* b ^* color space representing the color tone of the normal reflected light at the 5° incident angle of the CIE standard light source D65, and passes These a ^* and b ^* values evaluate the hue of reflected light.

Measurements were performed at 3 points in the longitudinal direction of the roll (the front end portion, the center portion, and the tail portion of the coating roll) and 3 points in the transverse direction of each of these 3 points, that is, a total of 9 points.

In each film, the a ^* and b ^* values were respectively averaged to obtain a central value. The difference (ΔA) between the maximum value and the minimum value of each a ^* value or b ^* value is divided by this center value and multiplied by 100 to obtain the hue change rate. The rate of change was evaluated at the following four levels. Use the greater rate of change in the a ^* and b ^* values for the evaluation:

AA: 0-8%;

A: 8-20%;

B: 20-30%;

C: 30% or more.

(7) Weather resistance (color tone change)

The weathering test was conducted with a sunlight weathering tester (S-80, manufactured by Suga Shiken-ki Co., humidity: 50%) at an exposure time of 200 hours.

On the samples before and after the weathering test, the reflection spectrum of the incident light at an incident angle of 5° was measured in the same manner as in the measurement of the specular reflectance, and then calculated in the wavelength range of 380-780nm in the CIE chromaticity diagram Reflect the hue of light and determine the change in chromaticity between before and after the weathering test. On the chromaticity diagram, determine the distance ΔE from the center point of each sample to the hue point, and evaluate the difference ΔE between before and after the weathering test at the following four levels:

AA: ΔE is 8 or less;

A: ΔE is 8-15;

B: ΔE is 15-25;

C: ΔE is 25 or more.

Table 13 sample number Anti-reflection film No. Cellulose Acylate Substrate low refractive index layer Specular reflectance (%) Anti-glare performance Adhesive properties Steel wool scratch resistance Dustproof performance Uniformity of tone Weather resistance (shade change) Example C1a HK-01 CA1-1 LL-1 1.72 B AAA A A AAA AAA Example C1b HK-02 CA1-1 LL-2 1.76 B AAA A B AAA AAA Example C1c HK-03 CA1-1 LL-3 1.70 B AAA A A A AAA Comparative Example C1-5 HFR1 CAR1-1 LL-1 1.72 B A A B B A Comparative Example C1-6 HFR2 CAR1-2 LL-1 1.73 B B A B B B Comparative Example C1-7 HFR3 CAR1-3 LL-1 1.69 B A A B B B Comparative Example C1-8 HFR4 CAR1-4 LL-1 1.77 B C A B B B Comparative Example C1-9 HFR5 CA1-1 LR-1 2.03 B AAA C A A A Comparative Example C1-10 HFR6 CA1-1 LR-1 2.15 B AAA A B A A

Comparative Examples C1-5 to C1-8 Utilizing the comparative substrates, the coated films were inferior in adhesive properties, dustproof properties, and weather resistance, and had lower color tone uniformity.

Furthermore, the comparison examples C1-9 in which the hollow silica particles were not contained in the low-refractive index layer and the comparative examples C1-10 in which the hollow silica particles were replaced with non-hollow silica particles (ordinary silica particles) The anti-reflection performance is poor.

Also, the transmission image of the antireflection film of Example C1a is clearer than that of Comparative Examples C1-7 and the transmission image performance is satisfactory.

As explained above, the antireflection film of the present invention is particularly excellent in antireflection performance, the adhesion deficiency obtained thereby is improved, and the scratch resistance, light resistance, transmission imaging performance and other characteristics mentioned above are satisfactory .

[Example C-2]

<Preparation of anti-reflection film>

[Example C-2a]

(Preparation of anti-reflection film (HK-11))

(Preparation of hard coat layer)

The following components were poured into a mixing tank and stirred to obtain a hard coat coating liquid.

750.0 parts by weight of trimethylolpropane triacrylate (TMPTA, manufactured by Nippon Kayaku Co.), 270.0 parts by weight of poly(glycidyl methacrylate) with a weight average molecular weight of 15,000, 730.0 parts by weight of methyl Ethyl ketone, 500.0 parts by weight of cyclohexanone, and 50.0 parts by weight of a photopolymerization initiator (Irgacure 184, manufactured by NipponCiba-Geigy Ltd.), were stirred and filtered through a polypropylene filter with a pore size of 0.4 μm to obtain a hard coat layer coating solution.

The cellulose acylate film (CA1-1) prepared in Example C-1 was developed and coated with a hard coat coating liquid with a gravure coater. After drying at 100° C., an air-cooled metal halide lamp (manufactured by Eyegraphics Co.) of 160 W/cm was used at an irradiation intensity of 400 mW/cm ² and an irradiation amount of 300 mJ/cm in an atmosphere of an oxygen concentration of 1.0 volume % under nitrogen flushing. It was irradiated with ultraviolet light of ² to harden the coating, thereby obtaining a film (HKH-01) having a hard coat layer with a thickness of 8 μm.

(Preparation of High Refractive Index Layer)

^* Preparation of titanium dioxide particle dispersion for high refractive index layer

As the silica particles, titanium dioxide particles containing cobalt and subjected to surface treatment of aluminum hydroxide and zirconium hydroxide (MPT-129C, manufactured by Ishihara Sangyo Co., TiO ₂ : Co ₃ O ₄ : _{Al 2} O ₃ : ZrO ₂ = 90.5:3.0:4.0:0.5 weight ratio).

To 257.1 parts by weight of these particles, 41.1 parts by weight of the following dispersant and 701.8 parts by weight of cyclohexanone were added and dispersed in a bead mill to obtain a titanium dioxide dispersion having a weight average particle diameter of 70 nm.

Dispersant

^* Preparation of high refractive index layer-1

To 99.1 parts by weight of the aforementioned titanium dioxide dispersion, 68.0 parts by weight of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by NipponKayaku Co.), 3.6 parts by weight of a photopolymerization initiator (Irgacure 907 ), 1.2 parts by weight of photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co.), 279.6 parts by weight of methyl ethyl ketone and 1049.0 parts by weight of cyclohexanone and stirred. After being sufficiently stirred, the mixture was filtered through a polypropylene filter with a pore size of 0.4 μm to obtain a coating liquid for High Refractive Index Layer-1.

The coating solution for the high refractive index layer-1 was applied onto the hard coat layer (HKH-01) with a gravure coater. After drying at 90° C. for 30 seconds, an air-cooled metal halide lamp (manufactured by Eyegraphics Co.) of 180 W/cm was used at an irradiation intensity of 400 mW/cm in an atmosphere of ^nitrogen flushing to obtain an oxygen concentration of 1.0% by volume or less The coating was hardened by irradiating it with ultraviolet light with an irradiation amount of 400 mJ/cm ² . A film (HKM-01) with a high refractive index layer was produced in this way.

After curing, High Refractive Index Layer-1 had a refractive index of 1.630 and a thickness of 67 nm.

^* Preparation of high refractive index layer-2

To 469.8 parts by weight of the aforementioned titanium dioxide dispersion, 40.0 parts by weight of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by NipponKayaku Co.), 3.3 parts by weight of a photopolymerization initiator (Irgacure907, manufactured by Nippon Ciba-Geigy Ltd.), 1.1 parts by weight of a photosensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co.), 526.2 parts by weight of methyl ethyl ketone, and 459.6 parts by weight of cyclohexanone were stirred. The mixture was then filtered through a polypropylene filter with a pore diameter of 0.4 μm to obtain a coating liquid for High Refractive Index Layer-2.

The coating liquid of the high refractive index layer-2 was applied onto the high refractive index layer (HKM-01) with a gravure coater to obtain a film having the high refractive index layer (HKK-01). A drying condition of 90° C. for 30 seconds was adopted for the high-refractive index layer, and an oxygen concentration of 1.0% by volume or less was obtained under nitrogen flushing with an air-cooled metal halide lamp (manufactured by Eyegraphics Co.) of 240 W/cm. In the atmosphere, the ultraviolet light curing conditions are 600mW/cm ² and 400mJ/cm ² irradiation.

After curing, High Refractive Index Layer-2 had a refractive index of 1.905 and a thickness of 107 nm.

(Preparation of anti-reflection film (HK-11))

Under the same processing conditions as obtaining the anti-reflection film (HK-11), the coating liquid LL-1 of the same low refractive index layer as in Example C-1a is coated on the high refractive index layer with a gravure coater (HKk-01) on.

[Example C-2b]

(Preparation of anti-reflection film (HK-12))

Prepared, coated and dried with the liquid of the hard coat layer (HKH-01), high refractive index layer-1 (HKM-01) and high refractive index layer-2 (HKK-01) in the aforementioned embodiment C-2a The substrate, the hard coat layer, the high-refractive-index layer-1 and the high-refractive-index layer-2 were prepared in the same manner.

(Preparation of Low Refractive Index Layer)

An antireflection film (HK-12) was obtained using the coating liquid LL-2 for the low refractive index layer in Example C-1b under the same coating and drying conditions as in Example C-1b.

[Example C-2c]

(Preparation of anti-reflection film (HK-13))

Prepared, coated and dried with the liquid of the hard coat layer (HKH-01), high refractive index layer-1 (HKM-01) and high refractive index layer-2 (HKK-01) in the aforementioned embodiment C-2a The substrate, the hard coat layer, the high-refractive-index layer-1 and the high-refractive-index layer-2 were prepared in the same manner.

(Preparation of Low Refractive Index Layer)

An antireflection film (HK-13) was obtained using the coating liquid LL-3 for the low refractive index layer in Example C-1c under the same coating and drying conditions as in Example C-1c.

[Comparative Example C2-1]-[Comparative Example C2-6]

Compared with the antireflection film (HK-11) of Example C-2a, the following comparative samples with different configurations were prepared (the substrate was the same as in Comparative Examples C1-5 to C1-10, but the configuration of the antireflection layer different):

(1) The same sample as in Example C-2a, except that the cellulose acylate substrate CAR1-1 was used (the film is labeled with HFR11)

(2) The same sample as in Example C-2a, except that cellulose acylate substrate CAR1-2 (HFR12) was used;

(3) The same sample as in Example C-2a, except that cellulose acylate substrate CAR1-3 (HFR13) was used;

(4) The same sample as in Example C-2a, except that cellulose acylate substrate CAR1-4 (HFR14) was used;

(5) Prepare the coating solution (LR-1) for the low-refractive index layer by removing the hollow silica therein and increasing the corresponding weight of fluoropolymer and apply the solution in the same manner as in Example C-2a to form samples (HFR15); and

(6) Preparation of low refraction by substituting the same amount of non-hollow (ordinary) silica particles (different particle size grade from MEK-ST, particle size: 45 μm, manufactured by Nissan Chemical Industries Ltd.) in which hollow silica The coating liquid (LR-2) of the rate layer was coated and the sample (HFR16) formed by this liquid was coated in the same manner as Example C-2a.

(Evaluation of anti-reflection film)

The obtained film was evaluated for items other than the antiglare performance in the same manner as in Example C-1, and the results are shown in Table 14.

Table 14 sample number Anti-reflection film No. Cellulose Acylate Substrate low refractive index layer Anti-reflective properties Adhesive properties Steel wool scratch resistance Dustproof performance Uniformity of tone Weather resistance (shade change) Example C-2a HK-11 CA1-1 LL-1 0.33 AAA A A AAA AAA Example C-2b HK-12 CA1-1 LL-2 0.36 AAA A B AAA AAA Example C-2c HK-13 CA1-1 LL-3 0.38 AAA A A AAA AAA Comparative Example C2-1 HFR11 CAR1-1 LL-1 0.30 A A B B A Comparative Example C2-2 HFR12 CAR1-2 LL-1 0.33 B A B A B Comparative Example C2-3 HFR13 CAR1-3 LL-1 0.39 A A B A B Comparative Example C2-4 HFR14 CAR1-4 LL-1 0.37 C A B A B Comparative Example C2-5 HFR15 CA1-1 LR-1 0.77 AAA C A AAA A Comparative Example C2-6 HFR16 CA1-1 LR-1 0.64 AAA A B AAA A

As a result of the evaluation, the antireflection films of Examples C-2a to C-2c of the present invention showed satisfactory antireflection performance, and the adhesive performance, steel wool scratch resistance, dustproof performance and color tone of the coated film Uniformity is also satisfactory. Also, these properties were not lowered even after the weathering test.

Comparative Examples C1-5 to C1-8 using the comparative substrate were inferior in adhesive properties and weather resistance of the coated film, and inferior in color tone uniformity.

Furthermore, the results of Comparative Example C2-5 containing no hollow silica particles in the low-refractive index layer and Comparative Example C2-6 in which the hollow silica particles were replaced with non-hollow silica particles (ordinary silica particles) The anti-reflection performance is poor.

As previously explained, the antireflection film of Example C-2 is particularly excellent in antireflection performance, the lack of adhesion associated therewith is also improved, and scratch resistance, light fastness, transmission imaging performance and other characteristics mentioned above Also satisfying.

The surface free energy and dynamic friction coefficient of the antireflection films of Examples C-1 and C-2 were measured below. The surface free energy was calculated from the contact angles of water and diiodomethane. The coefficient of kinetic friction was determined with a Heidon kinetic tribometer using a stainless steel ball with a diameter of 5 mm and under a load of 100 g on samples conditioned at 25°C and 60% RH.

Table 15 sample number Surface Free Energy (mN/m) dynamic friction coefficient Example C-1a Example C-2a Comparative Example C1-5 Comparative Example C2-1 22.323.527.628.0 0.090.080.240.21

[Example C-3]

<Preparation of substrate>

Cellulose acylate films CA2-1 to CA2-6 were prepared in the same manner as cellulose acylate film CA1-1 in Example C-1, except that the aliphatic ester plasticizer and the ultraviolet absorption were changed as shown in Table 16. agent. And the comparison films CAR2-1 to CAR2-3 were prepared by changing the preparation conditions and composition. The compositions and preparation conditions of these films are shown in Table 16.

Table 16 sample number film number Thickness (μm) polyol ester number UV absorber Drying air speed after casting for 1 second Drying air temperature (℃) Example C3-1 CA2-1 80 4 UV-2 15 50 Example C3-2 CA2-2 80 7 UV-2 15 50 Example C3-3 CA2-3 79 16 UV-2 15 50 Example C3-4 CA2-4 80 34 UV-2 15 50 Example C3-5 CA2-5 80 8 UV-2 15 50 Example C3-6 CA2-6 81 4 UV-3 15 50 Example C3-7 CA2-7 80 4 UV-4. 15 50 Comparative Example C3-1 CAR2-1 79 4 UV-2 twenty four 60 Comparative Example C3-2 CAR2-2 80 none UV-2 15 50 Comparative Example C3-3 CAR2-3 80 4 none 15 50

The ultraviolet absorbers in Table 16 are as follows.

UV-2: a copolymer of the aforementioned ultraviolet absorbing monomer UVM-1 and HPMA (weight average molecular weight: 8,300, ultraviolet absorbing monomer content: 32% by weight);

UV-3: a copolymer of the aforementioned ultraviolet absorbing monomer UVM-2 and MMA (weight average molecular weight: 12,000, ultraviolet absorbing monomer content: 54% by weight);

UV-4: a copolymer of the aforementioned ultraviolet absorbing monomer UVM-5 and MMA (weight average molecular weight: 8,400, ultraviolet absorbing monomer content: 50% by weight).

The obtained cellulose acylate film was subjected to the same evaluation as in Example C-1. The results are shown in Tables 17 and 18.

Table 17 sample number film number Thickness variation range (%) curly Raμm Rzμm Ra/Rz Smμm Ryμm Haze% Tear strength (g) optical defect Example C3-1 CA2-1 ±2.4 -4.5 0.008 0.018 0.44 0.153 0.024 0.27 17 0.5 Example C3-2 CA2-2 ±2.5 -5.1 0.007 0.019 0.37 0.155 0.022 0.24 18 0.4 Example C3-3 CA2-3 ±2.4 -4.3 0.008 0.017 0.47 0.161 0.025 0.24 15 0.4 Example C3-4 CA2-4 ±2.6 -4.6 0.009 0.018 0.50 0.157 0.022 0.23 17 0.6 Example C3-5 CA2-5 ±2.2 -4.3 0.006 0.016 0.38 0.160 0.023 0.25 19 0.4 Example C3-6 CA2-6 ±2.4 -4.8 0.008 0.028 0.29 0.247 0.125 0.46 18 0.4 Example C3-7 CA2-7 ±2.3 -5.3 0.009 0.027 0.33 0.256 0.124 0.57 17 0.6 Comparative Example C3-1 CAR2-1 ±5.1 -9.6 (Cannot be measured due to lack of planarity) Comparative Example C3-2 CAR2-2 ±3.9 -7.6 0.009 0.033 0.27 0.245 0.175 0.30 16 1.6 Comparative Example C3-3 CAR2-3 ±4.2 -5.3 0.008 0.031 0.26 0.248 0.182 0.27 16 1.5

Table 18 sample number Moisture permeability (g/m ² ·24h) Exudation performance (%) Example C3-1 165 1.4 Example C3-2 157 0.9 Example C3-3 148 1.5 Example C3-4 160 0.8 Example C3-5 143 1.1 Example C3-6 170 0.9 Example C3-7 145 1.1 Comparative Example C3-1 223 2.4 Comparative Example C3-2 266 2.8 Comparative Example C3-3 248 2.6

On the cellulose acylate film of Example C-3, the light-diffusing layer and low refractive index layer of Example C-1 or the hard coat layer of Example C-2, high refractive index layer-1, High-refractive-index layer-2 and low-refractive-index layer. The coatings are shown in Table 19, and the results of the same evaluation as in Example C-1 are shown in Table 20.

Table 19 sample number film number light diffusing layer low refractive index layer hard coat High Refractive Index Layer-1 High Refractive Index Layer-2 low refractive index layer Example C3-11 CA2-1 Example C-1a Example C-1a none none none none Example C3-12 CA2-2 Example C-1a Example C-1a none none none none Example C3-13 CA2-3 Example C-1a Example C-1a none none none none Example C3-14 CA2-4 Example C-1a Example C-1a none none none none Example C3-15 CA2-5 Example C-1a Example C-1a none none none none Example C3-16 CA2-6 Example C-1a Example C-1a none none none none Example C3-17 CA2-7 Example C-1a Example C-1a none none none none Comparative Example C3-11 CAR2-1 Example C-1a Example C-1a none none none none Comparative Example C3-12 CAR2-2 Example C-1a Example C-1a none none none none Comparative Example C3-13 CAR2-3 Example C-1a Example C-1a none none none none Example C3-18 CA2-1 none none Example C-2a Example C-2a Example C-2a Example C-2a Example C3-19 CA2-2 none none Example C-2a Example C-2a Example C-2a Example C-2a Example C3-20 CA2-6 none none Example C-2a Example C-2a Example C-2a Example C-2a Example C3-21 CA2-7 none none Example C-2a Example C-2a Example C-2a Example C-2a Comparative Example C3-14 CAR2-1 none none Example C-2a Example C-2a Example C-2a Example C-2a Comparative Example C3-15 CAR2-2 none none Example C-2a Example C-2a Example C-2a Example C-2a Comparative Example C3-16 CAR2-3 none none Example C-2a Example C-2a Example C-2a Example C-2a

Table 20 sample number Anti-reflection film No. Anti-reflective properties Adhesive properties Steel wool scratch resistance Dustproof performance Uniformity of tone Weather resistance (shade change) Example C3-11 HK-21 1.75 AAA A A AAA AAA Example C3-12 HK-22 1.70 AAA A B AAA AAA Example C3-13 HK-23 1.74 AAA A A AAA AAA Example C3-14 HK-24 1.68 AAA A A AAA AAA Example C3-15 HK-25 1.79 AAA A A AAA AAA Example C3-16 HK-26 1.65 AAA A A AAA AAA Example C3-17 HK-27 1.66 AAA A A AAA AAA Comparative Example C3-11 HFR21 1.67 A A B B A Comparative Example C3-12 HFR22 1.71 B A B A B Comparative Example C3-13 HFR23 1.70 A A B A B Example C3-18 HK-28 0.33 AAA A A AAA AAA Example C3-19 HK-29 0.36 AAA A B AAA AAA Example C3-20 HK-30 0.38 AAA A A AAA AAA Example C3-21 HK-31 0.38 AAA A A AAA AAA Comparative Example C3-14 HFR24 0.30 A A B B A Comparative Example C3-15 HFR25 0.33 B A B A B Comparative Example C3-16 HFR26 0.39 A A B A B

As shown in the table, the antireflection film of Example C-3, using the plasticizer and ultraviolet absorber of the present invention and hollow silica in the low refractive index layer, is the same as that of Examples C-1 and C-2 , showing a range of variation in film thickness and reduced curling, and excellent adhesive properties, dustproof properties, color tone uniformity, and weather resistance.

Also, the anti-glare performance evaluated by the aforementioned method for Examples C3-11 to C3-17 and Comparative Examples C3-11 to C3-13 was rank B in all samples.

[Example C-4]

<Preparation of anti-reflection film>

(Preparation of conductive layer)

On the cellulose acylate film shown in Table 21, Peltron C-4456-S7 (trade name of ATO-dispersed hard coat agent, solid: 45%, manufactured by Pelnox Corp.) was coated, dried and hardened by ultraviolet irradiation , forming a conductive layer (EL-1) with a thickness of 1 μm. The conductive layer has a surface resistivity of about 10 ⁸ Ω/sq.

After the sample was left to stand under the condition of 25°C/65%RH for 1 hour, the surface resistivity was measured with a resistivity meter MCP-HT260 manufactured by Mitsubishi Chemical Corp.

Furthermore, the sample showed a haze of 13.8%, a light transmittance of 76%, and surface properties of Ra 0.014, Rz 0.041 and Ry 0.058 (the measurement method is the same as explained above).

(Preparation of Light Diffusing Layer)

A light-diffusing layer was prepared in the same manner as that of Example C-1a.

(Coating liquid LL-4 for low refractive index layer)

Add 130 parts by weight of thermally crosslinkable fluoropolymer (JTA113, solid concentration 6%, manufactured by JSR Corp.) with a refractive index of 1.42, 5 parts by weight of silica sol (silica MEK-ST, average particle diameter 15nm, solid content 30%, manufactured by NissanChemical Industries Ltd.), 15 parts by weight of hollow silica (CS60-IPA, average particle diameter: 60nm, shell thickness: 10nm, refractive index: 1.31, 20% by weight of isopropyl Alcohol dispersion, manufactured by Catalysts & Chemicals Ind.Co.), 6 parts by weight of the following sol liquid a, 50 parts by weight of methyl ethyl ketone and 60 parts by weight of cyclohexanone were mixed and passed through a polyamide with a pore size of 1 μm Filtration was carried out with an acrylic filter to obtain coating liquid LL-4 for a low-refractive index layer.

<sol liquid a>

In a reactor equipped with a stirrer and a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co.) were mixed and 3 parts of aluminum diisopropylacetate (Chelope, Hope Chemical Co.), then 30 parts of ion-exchanged water was added and the mixture was reacted at 60° C. for 4 hours, and cooled to room temperature to obtain a sol liquid. Its weight-average molecular weight is 1,600, and among components equal to or greater than oligomers, components with a molecular weight of 1,000-20,000 account for 100%. Furthermore, gas chromatographic analysis revealed that no acryloxypropyltrimethoxysilane used as a raw material remained at all.

Add 5.6 parts by weight of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, manufactured by Nippon Kayaku Co.), 1.4 parts by weight of a mixture of the aforementioned fluoropolymer (FP-1), 20.0 parts by weight of hollow bismuth Silicon oxide (CS60-IPA, 20% by weight of isopropyl alcohol dispersion, manufactured by Catalysts & Chemicals Ind. Co.), 0.7 parts by weight of RMS-033 (reactive polysiloxane, manufactured by Gelest Inc.), 0.2 A photopolymerization initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals Inc.), 6.2 parts by weight of sol liquid a (as described above) and 315.9 parts by weight of methyl ethyl ketone were mixed in parts by weight. After sufficiently stirring, the mixture was filtered through a polypropylene filter with a pore diameter of 1 μm to obtain a low-refractive index layer coating liquid LL-5.

^* Coating of low refractive index layer

Coating liquids LL-4 and LL-5 were respectively coated under the condition that the number of rolls was 30 rpm and the conveying speed was 15 m/min through a roller and a scraper with a gravure pattern of 180 lines/inch and a depth of 40 μm. Clothed on the light-diffusing layer, then dried at 120°C for 150 seconds, then dried at 140°C for 8 minutes, and irradiated with UV light at a power of 240mW/ ^cm2 and an irradiation amount of 900mJ/ ^cm2 under nitrogen flushing, A low-refractive-index layer with a thickness of 90 nm was thus obtained.

As shown in Table 21, the aforementioned coating solutions and the coating dopes of Examples C-1a and C-2a were combined to prepare antireflective films.

Table 21 sample number Cellulose Acylate Film No. conductive layer light diffusing layer low refractive index layer hard coat High Refractive Index Layer-1 High Refractive Index Layer-2 low refractive index layer Example C4-11 CA2-1 EL-1 Example C-1a Example C-1a (LL-1) none none none none Example C4-12 CA2-2 EL-1 Example C-1a Example C-1a (LL-1) none none none none Example C4-13 CA2-6 EL-1 Example C-1a Example C-1a (LL-1) none none none none Example C4-14 CA2-7 EL-1 Example C-1a Example C-1a (LL-1) none none none none Example C4-15 CA2-1 EL-1 Example C-1a Example C-4, LL-4 none none none none Example C4-16 CA2-1 EL-1 Example C-1a Example C-4, LL-5 none none none none Comparative Example C4-11 CAR2-1 EL-1 Example C-1a Example C-1a (LL-1) none none none none Comparative Example C4-12 CAR2-2 EL-1 Example C-1a Example C-1a (LL-1) none none none none Comparative Example C4-13 CAR2-3 EL-1 Example C-1a Example C-1a (LL-1) none none none none Example C4-17 CA2-1 EL-1 none none Example C-2a Example C-2a Example C-2a Example C-2a Example C4-18 CA2-2 EL-1 none none Example C-2a Example C-2a Example C-2a Example C-2a Example C4-19 CA2-6 EL-1 none none Example C-2a Example C-2a Example C-2a Example C-2a Example C4-20 CA2-7 EL-1 none none Example C-2a Example C-2a Example C-2a Example C-2a Comparative Example C4-14 CAR2-1 EL-1 none none Example C-2a Example C-2a Example C-2a Example C-2a Comparative Example C4-15 CAR2-2 EL-1 none none Example C-2a Example C-2a Example C-2a Example C-2a Comparative Example C4-16 CAR2-3 EL-1 none none Example C-2a Example C-2a Example C-2a Example C-2a

The obtained antireflection film was evaluated in the same manner as in Example C-1. The results are shown in Table 22.

Table 22 sample number Anti-reflection film No. Anti-reflective properties Adhesive properties Steel wool scratch resistance Dustproof performance Uniformity of tone Weather resistance (shade change) Example C4-11 HK-41 1.74 AAA A AAA AAA AAA Example C4-12 HK-42 1.70 AAA A A AAA AAA Example C4-13 HK-43 1.75 AAA A AAA AAA AAA Example C4-14 HK-44 1.69 AAA A AAA AAA AAA Example C4-15 HK-45 1.78 AAA A AAA AAA AAA Example C4-16 HK-46 1.67 AAA A AAA AAA AAA Comparative Example C4-11 HFR41 1.68 A A A B A Comparative Example C4-12 HFR42 1.66 B A A A B Comparative Example C4-13 HFR43 1.70 A A A A B Example C4-17 HK-47 0.36 AAA A AAA AAA AAA Example C4-18 HK-48 0.37 AAA A A AAA AAA Example C4-19 HK-49 0.39 AAA A AAA AAA AAA Example C4-20 HK-50 0.38 AAA A AAA AAA AAA Comparative Example C4-14 HFR44 0.42 A A A B A Comparative Example C4-15 HFR45 0.33 B A A A B Comparative Example C4-16 HFR46 0.38 A A A A B

The results shown in Table 22 indicate that the antireflection films of Examples C4-11 to C4-20 having the conductive layer have improved dustproof performance and other characteristics are similar to those of Examples C1-C3.

Also, the anti-glare properties evaluated by the aforementioned method for Examples C4-11 to C4-16 and Comparative Examples C4-11 to C4-13 were rank B in all samples.

Weather resistance (change in reflectance) was evaluated for the antireflection film of Example C-4 shown in Table 23, which also shows the evaluation results, in the following manner.

^* Evaluation of weather resistance (change in reflectance)

The specular reflectance at an incident angle of 5° and an output angle of -5° in the wavelength range of 380-780 nm was measured with a spectrophotometer V-550 (manufactured by JASCO Corp.) equipped with an adapter ARV-474, and the following The difference (ΔR) between the average reflectance before and after the weathering test is evaluated on four levels:

AA: ΔR is 0.1% or less;

A: ΔR is 0.1-0.2%;

B: ΔR is 0.2-0.4%;

C: ΔR is 0.4% or more.

Table 23 sample number Anti-reflective film No. Lightfastness (change in reflectance) Example C4-17 HK-47 AAA Example C4-18 HK-48 AAA Example C4-19 HK-49 A Example C4-20 HK-50 A Comparative Example C4-14 HFR44 B Comparative Example C4-15 HFR45 B Comparative Example C4-16 HFR46 B

The results shown in Table 23 illustrate that the antireflection films of Examples C4-17 to C4-20 of the present invention have excellent weather resistance.

[Example C-5]

(Preparation of protective film for polarizing plate)

The antireflection film prepared in Example C-1, C-2, C-3 or C-4, on the surface of the substrate opposite to the antireflection layer of the present invention, is subjected to saponification treatment by coating a saponification solution, and the saponification The solution was an alkaline solution composed of 57 parts by weight of potassium hydroxide, 120 parts by weight of propylene glycol, 535 parts by weight of isopropanol and 288 parts by weight of water and kept at 40°C.

The alkali solution on the saponified surface of the substrate is fully rinsed off with water, and fully dried at 100°C. In this way, an antireflection film used as a protective film of a polarizing plate was produced.

Iodine adsorption was performed by soaking a polyvinyl alcohol film (manufactured by Kuraray Co.) having a thickness of 75 μm in an aqueous solution consisting of 1000 g of water, 7 g of iodine, and 105 g of potassium iodide for 5 minutes. Then, the film was uniaxially stretched 4.4 times in the longitudinal direction in a 4% by weight aqueous solution of boric acid, and dried in the stretched state to obtain a polarizing sheet.

Using a polyvinyl alcohol-based adhesive, the surface of the polarizing sheet was adhered to the saponified surface of the cellulose acylate film (protective film for the polarizing plate) of the antireflection film. Using the same polyvinyl alcohol-based adhesive, the other surface of the polarizing sheet was adhered to a similarly saponified cellulose acylate film (TD-80UF, manufactured by Fuji Photo Film Co.) to obtain the results shown in Table 24. Polarizer shown (for side viewing).

Table 24 Sample No. (Polarizer on viewing side) Anti-reflection film Examples C5-1-C5-3 HK-01-03 Examples C5-4-C5-6 HK-11-13 Examples C5-7-C5-17 HK-21-31 Examples C5-18-C5-27 HK-41-50

(Evaluation of image display equipment)

IPS, VA equipped with polarizers of the invention thus prepared (Examples C5-1-C5-3, C5-4-C5-16, C5-7-C5-17 and C5-18-C5-27) Transmissive, reflective, and semi-transmissive liquid crystal display devices of the OCB and OCB modes have excellent antireflection performance and exhibit extremely excellent visibility.

[Example C-6]

(Preparation of Polarizer)

An optical compensation film (wide field of view film A 12B, manufactured by FujiPhoto Film Co.) with an optical compensation layer, wherein the disc shape of the disc structure unit is inclined towards the surface of the substrate and the disc face of the disc structure unit and the surface of the base The angle between varies with the depth of the optically anisotropic layer, and on the surface of the substrate opposite to the optically compensating layer, undergoes a saponification process similar to that of Example C-5.

Using a polyvinyl alcohol-based adhesive, the surface of the polarizing sheet produced in Example C-5 was adhered to the saponified surface of the cellulose acylate film (protective film for the polarizing plate) of the antireflection film shown in Table 25 superior. The other surface of the polarizing sheet was adhered to the similarly saponified surface of the triacetylcellulose film of the aforementioned optical compensation film using the same polyvinyl alcohol-based adhesive. Table 25 shows the antireflection film used and the obtained polarizing plate. A comparative example is also shown.

Table 25 Polarizer No. Anti-reflection film 6H-1 (the present invention) HK-01 6R-1 (comparative example) HFR1

<Liquid crystal display device>

(TN mode liquid crystal display device)

In a 20-inch TN-mode liquid crystal display device (TH-20TA3, manufactured by Matsushita Electric Co.), the polarizing plate on the viewing side was replaced with the aforementioned polarizing plate (6H-1 or 6R-1), which was attached with an acrylic adhesive The viewing side was attached in such a way that the optically anisotropic layer was on the liquid crystal cell side. And on the backlight side, the lower backlight side polarizing plate (BHB) was adhered with an adhesive in such a manner that the optically anisotropic layer was located on the liquid crystal cell side. The transmission axis of the polarizer on the viewing side and the transmission axis of the polarizer on the backlight side are mounted to form an O-mode.

The backside light-side polarizing plate (BHB) is prepared by preparing a polarizing sheet in the same manner as in Example C-5, and then adhering a cellulose acylate film (TD80UF) through a saponification process on it with a polyvinyl alcohol-based adhesive It is prepared by adhering the aforementioned saponified optical compensation film on the other surface of the polarizing sheet.

(LCD in OCB mode)

A polyimide film was provided as an alignment film on a glass substrate with ITO electrodes, and subjected to rubbing treatment. The two glass substrates thus obtained faced each other with rubbing directions parallel to each other and with a cell gap of 6 μm. A liquid crystal compound (ZLI1132, manufactured by Merck Inc.) having Δn of 0.1396 was poured into the cell gap to obtain a bend-aligned liquid crystal cell. On the produced bend-oriented unit in laminated relationship, the aforementioned polarizer (6H-1 or 6R-1) was adhered to the viewing side of the unit with an adhesive in such a way that the optical compensation sheet was on the side of the liquid crystal unit, and On the backlight side, a backlight side polarizing plate (BHB) was adhered with an adhesive in such a way that the optically anisotropic layer was located on the liquid crystal cell side. The transmission axis of the polarizer on the viewing side and the transmission axis of the polarizer on the backlight side are mounted to form an O-mode.

(VA mode LCD)

In a 22-inch VA mode liquid crystal display device (TH22-LH10, manufactured by Matsushita Electric Co.), the polarizing plate on the observation side was replaced with the aforementioned polarizing plate (6H-1 or 6R-1) with an optically anisotropic layer The way on the side of the liquid crystal cell is adhered to the viewing side with an acrylic adhesive.

(IPS mode LCD monitor)

In a 20-inch IPS mode liquid crystal display device (W20-1c3000, manufactured by Hitachi Ltd.), the polarizing plate on the observation side was replaced with the aforementioned polarizing plate (6H-1 or 6R-1) with an optically anisotropic layer positioned on The way the liquid crystal cell side is attached to the viewing side with an acrylic adhesive.

<Image Display Performance of Liquid Crystal Display Device>

Image display performance was evaluated for each of the aforementioned liquid crystal display devices by the following items. The results are shown in Table 26.

Each of the corresponding comparative examples was equipped with a polarizing plate, and on the outermost surface of the polarizing plate on the observation side, the antireflection film of the present invention was not provided.

(Evaluation method of image display performance)

(1) Evaluation of unevenness of displayed image

Using a measuring instrument (EZ-contrast 160D, manufactured by ELDIM Ltd.), visually observe the image display unevenness of the black display (L1):

A: There is no inhomogeneity at all (no recognition among the 10 discriminators);

B: slightly non-uniform (identified by 1-5 out of 10 discriminators);

C: Unevenness is strongly generated (identified by 6 or more out of 10 discriminators).

(2) Evaluation of reflection of external light

Using fluorescence, the reflection of external light was evaluated by visual observation at the following four levels:

AA: Changes in reflection but no disturbance at all;

A: The reflection changes but there is almost no interference;

B: Changes in reflection interfere but are permissible;

C: Interference of changes in reflection.

(3) Contrast and viewing angle

A white display voltage of 2 V and a black display voltage of 6 V were applied to the liquid crystal cell of the liquid crystal display device, and the contrast ratio in the lateral direction (perpendicular to the rubbing direction of the cell) was investigated with a measuring instrument (EZ-contrast 160D, manufactured by ELDIM Ltd.) and viewing angles (the range of angles where the contrast ratio becomes 10 or higher):

AA: The change is completely non-disruptive;

A: There are changes but little interference;

B: Changes are disruptive but permissible;

C: Change interference.

(4) Hue change

Use the same instrument as the evaluation of "(3) contrast and viewing angle" to visually observe the level of hue change from the front to the viewing angle of 60° and evaluate according to the following criteria:

AA: The change is completely non-disruptive;

A: There are changes but little interference;

B: Changes are disruptive but permissible;

C: Change interference.

The image quality of displayed images was evaluated by the display devices of Examples C6-1 to C6-4 and Comparative Examples C-6a to C-6d in the aforementioned manner. The results are shown in Table 26.

Table 26 Example number Polarizer No. LCD mode Image unevenness external light reflection shades of black contrast angle of view Hue change up/down direction Oblique light leak on black display C6-1 6H-1 TN A A A A - - A A Comparative Example 6a 6R-1 TN A C A B - - C C C6-2 6H-1 OCB A A A AAA - - AAA A Comparative Example 6b 6R-1 OCB A C A A - - AAA B C6-3 6H-1 VA A A A - A - AAA AAA Comparative Example 6c 6R-1 VA A C A - B - AAA A C6-4 6H-1 IPS A A A - - A AAA AAA Comparative Example 6d 6R-1 IPS A C A - - B AAA AAA

The embodiment C6-1 of the TN-mode display device, compared with the comparative embodiment C6a without the polarizer protective film of the present invention, not only eliminates the external light reflection, but also changes the image contrast, viewing angle and color tone in the up/down direction is also improved, thereby providing satisfactory visibility.

The embodiment C6-2 of the OCB-mode display device, compared with the comparative embodiment C6b without the polarizer protective film of the present invention, not only eliminates the reflection of external light, but also significantly changes the image contrast and tone in the up/down direction improved, thereby providing satisfactory visibility.

The embodiment C6-3 of the VA-mode display device, compared with the comparative embodiment C6c without the polarizer protective film of the present invention, not only eliminates the reflection of external light, but also obtains a practically acceptable level of oblique contrast, and the hue Variations are enhanced, thereby providing increased visibility.

The embodiment C6-4 of IPS-mode display device, compared with the comparative embodiment C6d without the polarizer protective film of the present invention, not only eliminates external light reflection, but also improves the light leakage at the black image display place of high contrast to Practical acceptable visibility.

As explained above, in the liquid crystal display device equipped with the polarizing plate having the antireflection film of the present invention, displayed images with extremely satisfactory visibility are obtained.

[Example C-7]

A part of the antireflection film samples (HK-01, HK-02, HK-11, HK-23, HK-41 and HK-43) of Examples C-1 to C-4 were adhered to organic The front glass plate of the EL display device. As a result, reflection on the glass surface is suppressed, and a high-visibility display device can be obtained.

[Example C-8]

Each of the polarizers (6H-1) on the observation side in Example C-6 was made to have a λ/4 plate attached to the face of the polarizer opposite to the antireflection film, and adhered to the front glass plate of the organic EL display device superior. As a result, reflections on the glass surface and from the inside of the glass plate are suppressed, and an extremely high-visibility display device can be obtained.

<Example D>

Embodiment D-1 and comparative examples D1 and D2

<Preparation of anti-reflection film (AF)>

[Preparation of hard coat coating solution]

750.0 parts by weight of trimethylolpropane triacrylate (TMPTA, manufactured by Nippon Kayaku Co.), 270.0 parts by weight of poly(glycidyl methacrylate) with a weight average molecular weight of 3,000, 730.0 parts by weight of methyl Ethyl ketone, 500.0 parts by weight of cyclohexanone, and 50.0 parts by weight of a photopolymerization initiator (Irgacure 184, manufactured by NipponCiba-Geigy Ltd.), were stirred and filtered through a polypropylene filter with a pore size of 0.4 μm to obtain a hard coat layer coating solution.

[Preparation of Titanium Dioxide Particle Dispersion A]

As the titanium dioxide particles, titanium dioxide particles containing cobalt and subjected to surface treatment of aluminum hydroxide and zirconium hydroxide (MPT-129C, manufactured by Ishihara Sangyo Co.) were used.

To 257.1 parts by weight of these particles, 38.6 parts by weight of the following dispersant and 704.3 parts by weight of cyclohexanone were added and dispersed in a bead mill to obtain a titanium dioxide dispersion A having a weight average particle diameter of 70 nm.

Dispersant

[Preparation of Coating Liquid for Middle Refractive Index Layer]

88.9 parts by weight of the aforementioned titanium dioxide dispersion, a mixture of 58.4 parts by weight of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA), 3.1 parts by weight of Irgacure 907, and 1.1 parts by weight of Kayacure DETX (provided by Nippon Kayaku Co. ), 482.4 parts by weight of methyl ethyl ketone and 1869.8 parts by weight of cyclohexanone were stirred and filtered through a polypropylene filter with a pore size of 0.4 μm to obtain a coating solution for a medium refractive index layer.

[Preparation of Coating Liquid for High Refractive Index Layer]

586.8 parts by weight of the aforementioned titanium dioxide dispersion, 47.9 parts by weight of DPHA, 4.0 parts by weight of Irgacure 907, 1.3 parts by weight of Kayacure DETX, 455.8 parts by weight of methyl ethyl ketone and 1427.8 parts by weight of cyclohexanone were stirred, and It was filtered through a polypropylene filter with a pore size of 0.4 μm to obtain a coating liquid for a high refractive index layer.

[Preparation of Coating Liquid for Low Refractive Index Layer]

1.4 parts by weight of DPHA, 5.6 parts by weight of the fluorine-containing polymer (PF-1) of the following structure, 20.0 parts by weight of hollow silica as hollow particles (average particle diameter: 40nm, shell thickness: 7nm, refractive index : 1.31, 18% by weight in isopropanol), 0.7 parts by weight of reactive polysiloxane "RMS-033" (manufactured by Gelest Inc.), 6.2 parts by weight of the following sol liquid a, 0.2 parts by weight of Irgacure 907 and 315.9 parts by weight of methyl ethyl ketone were stirred and filtered through a polypropylene filter with a pore size of 1 μm to obtain a coating solution for the low refractive index layer

Fluoropolymer (PF-1)

Mw: 5×10 ⁴ (molar ratio)

[Preparation of sol liquid a]

In a reactor equipped with a stirrer and a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co.) It was mixed with 3 parts of ethyl diisopropylaluminum acetoacetate, and then 30 parts of ion-exchanged water was added, and the mixture was reacted at 60° C. for 4 hours and cooled to room temperature to obtain a sol liquid. Its weight-average molecular weight is 1,600, and among components equal to or greater than oligomers, components with a molecular weight of 1,000-20,000 account for 100%. Furthermore, gas chromatographic analysis revealed that no acryloxypropyltrimethoxysilane used as a raw material remained at all.

[Preparation of anti-reflection film (AF-1)]

On a cellulose triacetate film (TAC-TD80U, manufactured by Fuji PhotoFilm Co., Ltd., refractive index: 1.48) having a thickness of 80 μm, the hard coat coating liquid was coated with a gravure coater. After drying at 100° C., an air-cooled metal halide lamp (manufactured by Eyegraphics Co.) of 160 W/cm was used at an irradiation intensity of 400 mW/cm ² and an irradiation amount It was irradiated with ultraviolet light of 300 mJ/cm ² to harden the coating, thereby obtaining a hard coating layer having a thickness of 8 μm. On the obtained hard coat layer, a coating liquid for a medium refractive index layer, a coating liquid for a high refractive index layer, and a coating liquid for a low refractive index layer were successively coated with a gravure coater having three coating points.

The drying condition of the middle refractive index layer was 2 minutes at 100° C., and the ultraviolet curing condition was: illuminance 400 mJ/cm ² and irradiation amount 400 mW/cm ² , using a 180 W/cm air-cooled metal halide lamp (manufactured by Eyegraphics Co.) , an oxygen concentration of 1.0% by volume or less was obtained under nitrogen flushing. The medium index layer had a refractive index of 1.630 and a thickness of 67 nm after curing.

The drying conditions of the high refractive index layer are 1 minute at 90°C and 1 minute at 100°C, and the ultraviolet curing conditions are: irradiation intensity 600mJ/cm ² and irradiation amount 600mW/cm ² , using a 240W/cm air-cooled metal halide lamp (manufactured by Eyegraphics Co.), an oxygen concentration of 1.0% by volume or less was obtained under nitrogen flushing. The high refractive index layer had a refractive index of 1.905 and a thickness of 107 nm after curing.

On the high refractive index layer, using a microgravure roll with a diameter of 50 mm and a doctor blade with a gravure pattern with a line number of 180 lines/inch and a depth of 40 μm, at a rotation speed of the gravure roll of 30 rpm and a transport speed of 15 m/min The coating solution for the low-refractive index layer was down-coated, then dried at 120° C. for 150 seconds, and then dried at 140° C. for 8 minutes, and was heated with a 240 W/cm air-cooled metal halide lamp (manufactured by Eyegraphics Co.) Under nitrogen flushing, irradiate with ultraviolet light with an illumination intensity of 400mW/cm ² and an irradiation dose of 900mJ/cm ² to form a low refractive index layer (AL-1) with a thickness of 100nm, thereby obtaining an antireflection film.

[Preparation of comparative anti-reflection film (AFR)]

Antireflection films (AFR-1)-(AFR-3) of Comparative Examples D1-1-D1-3 were prepared in the same manner as in Example D-1, except that Example D-1 was changed as shown in Table 27 The hollow particles of the low refractive index layer in the antireflection film (AF-1) obtained the low refractive index layers (ALR-1)-(ALR-3).

Table 27 Anti-reflection film No. low refractive index layer layer number hollow particles layer thickness Layer Refractive Index Average Particle Size/Shell Thickness Ratio to Layer Thickness AF-1 AL-1 40nm/7nm 40% 100nm 1.43 AFR-1 ALR-1 no hollow particles - 100nm 1.46 AFR-2 ALR-2 25nm/4nm 25% 100nm 1.43 AFR-3 ALR-3 105nm/18nm 105% 100nm 1.43

[Evaluation of anti-reflection film]

The following items of the obtained antireflection film were evaluated. The results are shown in Table 28.

(haze)

Haze was measured with a haze meter (Model 1001DP, manufactured by Nippon Denshoku Kogyo Co.). Measurements were made at 5 points on each film sample and the average value calculated.

(average reflectance)

The spectral reflectance at an incident angle of 5° and an outgoing angle of -5° in the wavelength range of 380-780 nm was measured by a spectrophotometer V-550 (manufactured by Jasco Corp.) equipped with an adapter ARV-474, and calculated by The average reflectance at 450-650 nm evaluates the anti-reflection performance.

(surface energy)

As an index of surface stain resistance (fingerprint resistance), the surface energy of the samples was determined in the aforementioned manner after conditioning the samples at 25° C. and 60% RH for 2 hours.

(dynamic friction coefficient)

The surface lubricity was evaluated using the coefficient of kinetic friction. After the sample was conditioned at 25° C. and 60% RH for 2 hours, dynamic friction was measured with a dynamic friction meter Heidon-14 (manufactured by Shinto Kagaku Co.) using a stainless steel ball with a diameter of 5 mm under a load of 100 g and a speed of 60 cm/min. coefficient.

(clarity)

Visually observe inhomogeneities in the transmitted light of a sample placed between two polarizers in crossed Nicols arrangement:

A: There is no inhomogeneity at all (no recognition among the 10 discriminators);

B: slightly non-uniform (identified by 1-5 out of 10 discriminators);

C: Unevenness is strongly generated (identified by 6 or more out of 10 discriminators).

(color uniformity)

With a spectrophotometer V-550 (manufactured by JASCO Corp.) equipped with an adapter ARV-474, the specular reflectance was measured at an incident angle of 5°, an output angle of -5° in the wavelength range of 380-780 nm, and then used The reflectance spectrum measured in the wavelength range of 450-650nm, calculate the L ^* value, a ^* and b ^* value of the CIE1976L ^* a ^* b ^* color space representing the color tone of the normal reflected light at the 5° incident angle of the CIE standard light source D65 , so as to evaluate the hue of reflected light.

A film having a length of 1 m was used as a sample, and measurements were performed at three points at the center of the roll and at both ends in the longitudinal and transverse directions. Samples were taken from the front portion, center portion and tail portion of the applicator roll. Each value represents the central value of these measurement points, and the rate of change was obtained by dividing the difference between the maximum value and the minimum value by the central value and expressed in %. Evaluate according to the following four levels:

A: The rate of change is 10% or less;

B: The rate of change is greater than 10% but less than 20%;

C: The rate of change is 21% or more.

Table 28 Anti-reflection film No. Haze/reflectivity (%/%) Surface energy (mN/m) dynamic friction coefficient clarity Uniformity of tone AF-1 0.31/0.40 25 0.12 A A AFR-1 0.31/0.56 25 0.12 B A AFR-2 0.30/0.49 25 0.12 C B AFR-3 0.39/0.42 26 0.21 C C

The antireflective film (AF-1) corresponding to Example D-1 of the present invention showed low reflectance, and had a film surface with low surface energy and excellent water repellency. It also exhibited high image definition, color tone close to neutral, with satisfactory uniformity. The image definition of the comparative antireflective film (AFR-1) was poor. The contrast antireflection film (AFR-2) was inferior in sharpness and color tone of the image. The contrast antireflection film (AFR-3) was insufficient in image sharpness and color tone.

[Surface treatment of anti-reflection film (AF)]

In each of the antireflection films (AF-1) and (AFR-1)-(AFR-3), the surface of the cellulose acetate film opposite to the antireflection film is passed under an induction heating roller at a temperature of 60°C, The film surface is heated to 40 DEG C, then by bar coater with 12cc/ ^m The coating quantity coats the alkaline solution (S-1) of following composition, then the steam type far-infrared heater (by (manufactured by Noritake Co.) was left to stand for 15 seconds, and the purified water was coated with a coating amount of 3 cc/m ² by a similar bar coater. The film temperature in this operation was 40°C. Then rinse the film with water through a jet coater and squeeze out the water with an air knife for 3 times, and stand in a drying zone at 70°C for 5 seconds to dry.

^* Composition of alkaline solution (S-1)

Potassium Hydroxide 8.55% by weight

Water 23.235% by weight

Isopropanol 54.20% by weight

Surfactant K-1: C ₁₄ H ₂₉ O(CH ₂ CH ₂ O) ₂₀ 1.0% by weight

Propylene Glycol 13.0% by weight

Defoamer Surfinol DF110D (formed by Nisshin 0.015% by weight

Chemical Industries Manufactured)

The saponified surface of each film obtained had a contact angle with water in the range of 34-35° and a surface energy in the range of 62-63 mN/m.

<Preparation of polarizing plate with antireflection film>

[Polarizing sheet (H-1) and polarizing plate (P-1) of the present invention]

A PVA film with an average degree of polymerization of 2,400 and a thickness of 105 nm was pre-swelled in ion-exchanged water at 40°C for 60 seconds, and then, after the moisture on the surface was scraped off with a stainless steel blade, the concentration was adjusted to maintain a constant concentration. Soak in an aqueous solution containing 0.7g/L iodine, 60.0g/L potassium iodide and 5.0g/L boric acid at 40°C for 55 seconds, then adjust the concentration to maintain a constant concentration in an aqueous solution containing 42.5g/L boric acid and 30g/L boric acid L was soaked in an aqueous solution of potassium iodide at 40° C. for 90 seconds, and after scraping off excess liquid on both surfaces with a stainless steel blade, was charged into a tenter of the form shown in FIG. 7 . After stretching 100 m of this film 5 times in an atmosphere of 60° C., 95% RH at a transport speed of 4 m/min, the tenter was bent with respect to the stretching direction shown in FIG. 7 , and then the width was kept constant. The film was dried while shrinking in an atmosphere of 70° C. and removed from the tenter to obtain a polarizing sheet (H-1). The polarizing sheet (H-1) had a thickness of 19 μm and a moisture content of 2.5% by weight.

During the stretching operation for preparing the antireflection film, the temperature was kept within a variation range of 55±0.2° C. and the humidity was kept within a range of 95±1%. The PVA film had a moisture content of 32% by volume before starting stretching, and a moisture content of 2.5% by weight after drying.

The difference between the transport speeds of the tenter clips (clamps) on the left and right sides of the PVA film is less than 0.05%, and the centerline of the added film and the centerline of the film advancing to the next step form an angle of 46°. The condition that |L1-L2| is 0.7m and W is 0.7m is maintained such that |L1-L2|=W. The approximate stretching direction Ax-Cx at the tenter exit is inclined at 45° relative to the center line 22 of the film advancing to the next step. At the exit of the tenter frame, shrinkage and film deformation were not observed.

Then, after cutting the lateral side by 3 cm with a cutter, using an aqueous solution of 3% PVA (PVA-124H, manufactured by Kuraray Co.) as an adhesive, the surface of the polarizing sheet was adhered to the opposite surface of the antireflection film. Saponified the cellulose acylate film surface of the cellulose acylate film coated with the antireflection film (AF-1), and also adhered the other side of the polarizing sheet to the same cellulose acetate film as used to form the antireflection film and heated at 70° C. for 10 minutes to obtain a rolled polarizing plate (P-1) having an antireflection film with an effective width of 650 mm and a length of 100 m.

The obtained polarizing plate had an absorption axis inclined at 45° to the longitudinal direction.

[Comparative Polarizing Sheet (HR-1) and Comparative Polarizing Plate (PR-1)]

A PVA film with an average degree of polymerization of 2,400 and a thickness of 132 nm was pre-swelled in ion-exchanged water at 15°C for 48 seconds, and then, after wiping off the moisture on the surface with a stainless steel blade, was adjusted to maintain a constant concentration. Soak in an aqueous solution containing 0.9g/L iodine and 60.0g/L potassium iodide at 40°C for 55 seconds, then adjust the concentration to maintain a constant concentration in an aqueous solution containing 42.5g/L boric acid and 30g/L potassium iodide It was soaked at 40° C. for 90 seconds, and after scraping off excess liquid on both surfaces with a stainless steel blade, was charged into a tenter of the form shown in FIG. 1 . After stretching 100 m of this film 4.12 times in an atmosphere of 60° C., 95% RH at a transport speed of 4 m/min, the tenter was bent with respect to the stretching direction shown in FIG. 1 , and then the width was kept constant. The film was dried while shrinking in an atmosphere of 75° C. and removed from the tenter to obtain a comparative polarizing sheet (HR-1). The polarizing sheet had a thickness of 29 μm and a moisture content of 2.5% by weight. The stretching process was performed under the same conditions as in Example D-1.

Then, after cutting the lateral side by 3 cm with a cutter, using an aqueous solution of 3% PVA (PVA-124H, manufactured by Kuraray Co.) as an adhesive, the polarizing sheet was adhered to the Fujitac that had been saponified as described above. film (cellulose triacetate, retardation: 3.0 nm, thickness: 80 μm, manufactured by Fuji Photo Film Co.), and heated at 70°C for 10 minutes to obtain a roll-shaped contrast polarizing plate (PR -1).

The single sheet light transmittance and polarization degree of the polarizing sheet (H) were measured by a Shimadzu self-recording spectrophotometer UV3100.

The degree of polarization is determined by the following equation (22), where H0(%) represents the light transmittance when two polarizers whose absorption axes are in a matching state overlap, and H1(%) represents the two polarizations whose absorption axes are in a mutually orthogonal state Transmittance when sheets overlap.

Equation (22):

Degree of polarization = [(H0-H1)/(H0+H1)] ^1/2 × 100

Single plate transmittance and degree of polarization were corrected for visual acuity and the results are shown in Table 29.

Table 29 polarizing sheet Anti-reflection film No. Polarizer properties polarizing sheet preparation steps Film thickness (μm) Single sheet light transmittance (%) Polarizer No. Degree of polarization (%) Transmittance when crossing Nicols boric acid in staining solution drying temperature 700nm transmittance (%) 410nm transmittance (%) Example D-1 H-1 have 70°C 19 43.0 AF-1 P-1 99.97 0.08 0.07 Comparative Example D-1 HR-1 No 75°C 29 43.4 Fuji-tac ^* PR-1 99.9 0.34 0.31

^* Transparent protective film

Comparative Examples D2-1-D2-3

[Other comparative polarizers with anti-reflection film]

Comparative polarizers (PR-1)-(PR-3) with antireflection film were prepared in the same manner as in Example D-1 except for the polarizer (P-1) with antireflection film of Example D-1 The antireflective film (AF-1) was replaced with any of the comparative antireflective films (AFR-1)-(AFR-3). The combinations used are shown in Table 30.

Table 30 Polarizer No. Polarizing Sheet No. Anti-reflection film No. Example D-1 P-1 H-1 AF-1 Comparative Example D2-1 PR-1 H-1 AFR-1 Comparative Example D2-2 PR-2 H-1 AFR-2 Comparative Example D2-3 PR-3 H-1 AFR-3

[Properties of polarizer with antireflection film]

The following properties of each obtained polarizing plate were evaluated, and the results are shown in Table 31.

(Pencil hardness test)

As an index of scratch resistance, pencil hardness was evaluated according to JIS K-5400. The polarizing plate with the antireflection film was conditioned at a temperature of 25°C and a humidity of 60%RH for 2 hours, and measured at 5 points on the surface of the antireflection film under a load of 1 kg with a 3H measuring pencil defined in JIS S-6006, Visually evaluate the results according to the following levels:

A: No scratches were observed at all points;

B: 1 or 2 scratches;

C: 3 or more scratches.

(adhesive properties)

The cellulose acylate film was subjected to humidity conditioning for 2 hours under conditions of a temperature of 25°C and a humidity of 60%RH. Then, on the surface of the antireflection film of the cellulose acylate film, cut eleven notches in the longitudinal and transverse directions with a cutter to form 100 squares, and then glue a polyester adhesive tape (No. The adhesion test (manufactured by Nitto Denko Co.) was repeated 3 times, and the degree of peeling was visually observed and evaluated in the following four levels:

AA: No peeling was observed in all 100 squares;

A: Peeling was observed in 2 or less of 100 squares;

B: Peeling was observed in 3-10 out of 100 squares;

C: Peeling was observed in more than 10 out of 100 squares.

(steel wool scratch resistance)

On the antireflection film before and after exposure, after moving #0000 steel wool for 60 reciprocating cycles with a load of 500 g/cm ² , scratches were visually observed and evaluated in the following three levels:

A: No scratches at all;

B: The scratches formed are not easy to see;

C: Scratches are conspicuous.

(specular reflectance and tone uniformity)

The specular reflectance at an incident angle of 5° and an outgoing angle of -5° in the wavelength range of 380-780 nm was measured by a spectrophotometer V-550 (manufactured by Jasco Corp.) equipped with an adapter ARV-474, and then used in The reflectance spectrum measured in the wavelength range of 450-650nm calculates the L ^* , a ^* and b ^* values of the CIE1976L ^* a ^* b ^* color space representing the color tone of the normal reflected light at the 5° incident angle of the CIE standard light source D65, and passes These a ^* and b ^* values evaluate the hue of reflected light.

Measurements were performed at 3 points in the longitudinal direction of the roll (the front end portion, the center portion, and the tail portion of the coating roll) and 3 points in the transverse direction of each of these 3 points, that is, a total of 9 points.

In each film, the a ^* and b ^* values were respectively averaged to obtain a central value. The difference between the maximum and minimum values of each a ^* value or b ^* value is divided by this center value and multiplied by 100 to obtain the rate of hue change. The rate of change was evaluated at the following four levels. Use the greater rate of change in the a ^* and b ^* values for the evaluation:

AA: 0-8%;

A: 8-20%;

B: 20-30%;

C: 30% or more.

(Evaluation of weather resistance)

The weathering test was conducted with a sunlight weathering tester (S-80, manufactured by Suga Shiken-ki Co.) at a humidity of 50% for an exposure time of 200 hours.

On the sample after the weathering test, measure the specular reflectance and reflection spectrum of the incident light at an incident angle of 5° in the same manner as described above, and then calculate the hue of the reflected light in the wavelength range of 380-780nm in the CIE dyeability diagram , and compared with the specular reflectance and tint before the weathering test, to determine the change in specular reflectance and tint between before and after the weathering test. As for the change in hue, on the chromaticity diagram, the distance ΔE from the center point of each sample to the hue point was determined, and the difference ΔE between before and after the weathering test was evaluated at the following four levels:

AA: ΔE is 5 or less;

A: ΔE is 5-10;

B: ΔE is 10-15;

C: ΔE is 15 or more.

(change rate of optical transmittance and degree of polarization)

The polarizing plate with the antireflection film was allowed to stand in an atmosphere of 60° C. and 90% RH for 500 hours, and changes in optical transmittance and polarization degree were determined by comparing with the sample before standing.

Rate of change (%) = [(value before standing - value after standing)/value before standing] × 100

The level of change was evaluated according to the following criteria:

Change rate of optical transmittance Change rate of polarization degree

AA: Less than 2% Less than 1%

A: 2% or more but less than 3% 1% or more but less than 3%

C: 3% or greater 3% or greater

(Dimensional change rate)

The polarizing plate with the antireflection film was cut into a size of 50×50 mm and heated at 70° C. for 120 hours. Measure the size (La) and the size (Lb) of the test piece before heating and the size (Lb) after heating in the direction of absorption axis (MD) and polarization axis (TD), and determine the dimensional change rate (%) according to the following equation:

    Dimensional change rate = [(La-Lb)/Lb] × 100

Table 31 Polarizer No. pencil hardness adhesiveness Scratch resistance Uniformity of tone weather resistance Transmittance rate of change Polarization rate of change Dimensional change rate (%) MD direction TD direction Example D-1 P-1 A A A A AAA AAA AAA -0.55 -0.56 Comparative Example D2-1 PR-1 A C B A A AAA AAA -0.55 -0.56 Comparative Example D2-2 PR-2 B A C B A AAA AAA -0.56 -0.55 Comparative Example D2-3 PR-3 C C C C B AAA AAA -0.56 -0.57

The polarizing plate with antireflection film of Example D-1 showed satisfactory performance in terms of mechanical and optical film properties and durability. The samples of Comparative Examples D2-1-D2-3 were inferior in mechanical film properties and anti-reflection properties.

Example D-11

<Liquid crystal display device>

[Polarizer on the viewing side]

An optical compensation film (wide field of view film A 12B manufactured by FujiPhoto Film Co.) with an optical compensation layer, wherein the disk of the disk-shaped structural unit is inclined towards the surface of the substrate, and the disk-shaped surface of the disk-shaped structural unit and the surface of the substrate The angle between the surfaces varies with the depth of the optically anisotropic layer, and on the surface of the substrate opposite to the optical compensation layer, undergoes a saponification process similar to the conditions described above.

The surface of the cellulose triacetate film opposite to the antireflection film of the polarizer having the antireflection film was similarly subjected to alkali saponification. The saponified cellulose triacetate film surface of the optical compensation film and the polarizing plate with the antireflection film were bonded to each other using a polyvinyl alcohol-based adhesive, whereby a viewing side polarizing plate (SHB-1) was produced.

[Back polarizer]

A cellulose triacetate film (Fujitac TAC-TD80U) was used as the protective film on both sides of the aforementioned polarizing sheet (H-1), and one side was treated with alkali saponification as explained above, and glued with polyvinyl alcohol. Mixture Adhere the treated surface on the polarizing sheet (H-1) to obtain a polarizing plate. Then the surface of the cellulose triacetate film on one side of the polarizer and the surface of the optical compensation film (wide-view film A 12B), opposite to its optical compensation layer, were similarly treated with alkali saponification. These saponified surfaces were then bonded to each other with a polyvinyl alcohol-based adhesive to obtain a rear polarizing plate (BHB-1).

[TN mode liquid crystal display device]

In a 20-inch TN-mode liquid crystal display device (TH-20TA3, manufactured by Matsushita Electric Co.), the polarizing plate on the viewing side was replaced with the viewing-side polarizing plate (SHB-1) of the present invention, which was attached with an acrylic adhesive The viewing side was attached in such a way that the optically anisotropic layer was on the liquid crystal cell side. And on the backlight side, a backlight side polarizing plate (BHB-1) was adhered with an adhesive in such a manner that the optically anisotropic layer was located on the liquid crystal cell side. The transmission axis of the polarizer on the viewing side and the transmission axis of the polarizer on the backlight side are mounted to form an O-mode. Comparative Examples D11-1-D11-3

A TN-mode liquid crystal display device was prepared in the same manner as in Example D11, except that the viewing side polarizer (SHB-1) using the polarizer (P-1) with an antireflection film of the present invention was utilized to have an antireflection film The viewing side polarizer (SHB-R1)-(SHB-R3) of the comparison polarizer (PR-1)-(PR-3) is replaced.

[Image display performance of liquid crystal display device]

Image display performance was evaluated for each of the aforementioned liquid crystal display devices by the following items. The results are shown in Table 32.

(Evaluation of unevenness of displayed image)

Using a measuring instrument (EZ-contrast 160D, manufactured by ELDIM Ltd.), visually observe the image display unevenness of the black display (L1):

A: There is no inhomogeneity at all (none of the 10 discriminators recognize it);

B: slightly non-uniform (identified by 1-5 out of 10 discriminators);

C: Unevenness is strongly generated (identified by 6 or more out of 10 discriminators).

(Evaluation of reflection of external light)

Using fluorescence, the reflection of external light was evaluated by visual observation at the following four levels:

AA: Changes in reflection but no disturbance at all;

A: The reflection changes but there is almost no interference;

B: Changes in reflection interfere but are permissible;

C: Interference caused by reflection changes.

(Evaluation of the hue of the black display)

Using a measuring instrument (EZ-contrast 160D, manufactured by ELDIM Ltd.), the color tone change of the black display (L1) was observed with the naked eye:

AA: Not recognized at all (none of the 10 discriminators);

A: Slightly recognizable (1-2 out of 10 discriminators recognize);

B: Slightly recognizable (3-5 out of 10 discriminators recognize);

C: Can be strongly recognized (recognized by 6 or more out of 10 discriminators).

(contrast and viewing angle)

A white display voltage of 2 V and a black display voltage of 6 V were applied to the liquid crystal cell of the liquid crystal display device, and the contrast ratio in the lateral direction (perpendicular to the rubbing direction of the cell) was investigated with a measuring instrument (EZ-contrast 160D, manufactured by ELDIM Ltd.) and viewing angles (the range of angles where the contrast ratio becomes 10 or higher):

AA: The change is not disruptive at all;

A: There are changes but little interference;

B: Change interference but allowable;

C: Change interference.

(hue change)

Use the same instrument as the evaluation of "contrast and viewing angle" to visually observe the level of hue change from the front to the viewing angle of 60°, and evaluate according to the following criteria:

AA: The change is not disruptive at all;

A: There are changes but little interference;

B: Change interference but allowable;

C: Change interference.

The image quality of displayed images was evaluated by the display devices of Example D11 and Comparative Examples D11-1 to D11-3 in the aforementioned manner. The results are shown in Table 32.

Table 32 Observe side polarizer Polarizers with anti-reflection film Image unevenness external light reflection shades of black contrast angle of view Hue change Example D-11 SHB-1 P-1 A A A A A A Comparative Example D11-1 SHB-R1 P-R1 A C A B A A Comparative Example D11-2 SHB-R2 P-R2 B B A B A BA Comparative Example D11-3 SHB-R3 P-R3 B C B B B B

Example D-11 showed a satisfactory image display without unevenness over the entire displayed image, and showed a satisfactorily neutral bright image with little change in the color and tone of the black display.

Comparative Example D11-1 was poor in external light reflection and had insufficient contrast. Comparative Examples D11-2 and D11-3 were inferior in image unevenness, external light reflection, contrast and color tone change. Furthermore, unevenness in luminance occurs to result in insufficient uniformity of displayed images.

Therefore only the present invention can display bright and clear images.

Example D-12-D-13

Polarizers (P-2)-(P-3) with antireflection film were prepared in the same manner as in Example D-1, except that, in Examples D-1 and D-11, the The low refractive index layer (AL-1) in the antireflection film of the polarizing plate (P-1) was replaced with the lower low refractive index layer. These polarizing plates (P) were then used to prepare a viewing side polarizing plate as in Example D-11, and installed in a liquid crystal display device. These combinations are shown in Table 33.

(Low Refractive Index Layer AL-2)

Add 130 parts by weight of thermally crosslinkable fluoropolymer (JTA113, solid concentration: 6%, manufactured by JSR Corp.) with a refractive index of 1.42, 5 parts by weight of silica sol (MEK-ST, average particle diameter: 15nm, solid content: 30%, manufactured by Nissan Chemical Industries Ltd.), 15 parts by weight of hollow silica (CS60-IPA, average particle diameter: 60nm, shell thickness: 10nm, refractive index: 1.31, 20% by weight of iso Propanol dispersion (manufactured by Catalysts & Chemicals Ind.Co.), 6 parts by weight of the aforementioned sol liquid a, 50 parts by weight of methyl ethyl ketone and 60 parts by weight of cyclohexanone were mixed and passed through a pore diameter of 1 μm A polypropylene filter was used to obtain a coating solution for the low refractive index layer AL-2. Using this coating solution under the same coating conditions as in Example D-1, a low-refractive-index hardened film was formed with a thickness of 100 nm, thereby producing a polarizing plate (P-2) with an antireflection film.

The obtained antireflection polarizing plate had a surface with a surface energy of 21 mN/m and a dynamic friction coefficient of 0.12.

(Low Refractive Index Layer AL-3)

Add 130 parts by weight of thermally crosslinkable fluoropolymer (JN-7228, solid concentration: 6%, manufactured by JSR Corp.) with a refractive index of 1.42, 3.5 parts by weight of DHPMA, 15 parts by weight of silica sol MEK -ST, 15 parts by weight of hollow silica CS60-IPA, 6 parts by weight of the aforementioned sol liquid a, 3 parts by weight of active polysiloxane X22-164C, 50 parts by weight of methyl ethyl ketone and 60 parts by weight and mixed with cyclohexanone, and filtered through a polypropylene filter with a pore size of 1 μm to obtain a coating solution for the low refractive index layer AL-3. Using this coating solution under the same coating conditions as in Example D-1, a low-refractive-index hardened film was formed with a thickness of 100 nm, thereby producing a polarizing plate (P-3) with an antireflection film.

The obtained antireflection polarizing plate had a surface with a surface energy of 20 mN/m and a dynamic friction coefficient of 0.11.

[Polarizer on the viewing side]

Prepare polarizers (SHB2)-(SHB-3) on the viewing side in the same manner as in Example D-11, except that the polarizer (P-1) with an antireflection film in Example D-11 is prepared with the aforementioned Polarizers (P-2) and (P-3) with anti-reflection film were replaced.

[OCB mode liquid crystal display device]

A polyimide film was provided as an alignment film on a glass substrate with ITO electrodes, and subjected to rubbing treatment. The two glass substrates thus obtained faced each other with rubbing directions parallel to each other and with a cell gap of 6 μm. A liquid crystal compound (ZLI1132, manufactured by Merck Inc.) having Δn of 0.1396 was poured into the cell gap to obtain a bend-aligned liquid crystal cell. On the prepared bend alignment unit in a laminated manner, the aforementioned polarizing plate (SHB-2 or SHB-3) was adhered to the viewing side of the unit with an adhesive in such a manner that the optical compensation sheet was on the liquid crystal unit side, and On the backlight side, a backlight side polarizing plate (BHB-1) was adhered with an adhesive in such a manner that the optically anisotropic layer was located on the liquid crystal cell side. The transmission axis of the polarizer on the viewing side and the transmission axis of the polarizer on the backlight side are mounted to form an O-mode.

Table 33 low refractive index layer Observe side polarizer Back polarizer Example D-12 AL-2 SHB-2 BHB-1 Example D-13 AL-3 SHB-3 BHB-1

The properties of Examples D-12 and D-13 were evaluated in the same manner as Example D-11. All show satisfactory results comparable to the performance of Example D-11.

Example D-14

[Preparation of transparent protective film]

(Preparation of Fine Particle Dispersion (RL-1))

A mixture of the following components and zirconia beads having a diameter of 0.2 mm was wet dispersed in a bead mill to obtain a volume average particle diameter of 55 nm. The beads were separated from the obtained dispersion with a 200-mesh nylon cloth to obtain a particle dispersion (RL-1). The particle size distribution measured for the obtained particle dispersion confirmed that particles having a size of 300 nm or larger accounted for 0%.

The volume average particle diameter is measured with a particle size distribution measuring apparatus LA920 (manufactured by Horiba Mfg. Co.).

^* Composition of particle dispersion (RL-1):

Hydrophobic silica (Aerosil R812, methyl-modified, primary particle size: 2.00 parts by weight

7nm, manufactured by Nippon Aerosil Co.)

Cellulose triacetate (degree of substitution: 2.85, 6-position substitution: 0.90) 2.00 parts by weight

The following dispersant (DP-1) 0.25 parts by weight

Dichloromethane 78.70 parts by weight

Methanol 14.20 parts by weight

1-butanol 2.86 parts by weight

Dispersant (DP-1):

(Preparation of Cellulose Acylate Solution (A-1))

The mixture composed below was stirred and dissolved to obtain a cellulose acylate solution (A-1).

*Composition of Cellulose Acylate Solution (A-1)

100 parts by weight of cellulose triacetate propionate (acetate/propionate) with a degree of substitution of 2.70

=1/0.4)

The following plasticizer A (logP 4.18) 7.1 parts by weight

The following plasticizer B (logP 1.88) 3.6 parts by weight

The following plasticizer C (logP 3.73) 3.6 parts by weight

The following ultraviolet absorber: UV-1 0.5 parts by weight

The following ultraviolet absorber: UV-2 0.7 parts by weight

Dichloromethane 300 parts by weight

Methanol 54 parts by weight

1-butanol 11 parts by weight

Plasticizer A Plasticizer B

Plasticizer C

(Preparation of Coating Dope)

In 474 parts by weight of cellulose acylate solution (A-1), 15.3 parts by weight of particle dispersion (RL-1) was added under stirring, and then the mixture was stirred well, and left to stand at room temperature (25° C.) 3 hours, and the obtained heterogeneous gel-like solution was cooled at -70°C for 6 hours, heated and stirred at 50°C to obtain a fully dissolved coating dope.

The obtained coating dope was filtered at 50° C. with a filter paper (#63, manufactured by Toyo Filtering Paper Co.) with an absolute filtration accuracy of 0.01 mm, and then with a filter paper with an absolute filtration accuracy of 0.0025 mm (FH025, manufactured by Pall Inc. production) to filter and remove air bubbles to obtain a coating dope.

(solution casting process)

After the aforementioned preparation of the cellulose acylate solution, the coating dope thus obtained was cast with a belt caster used in the process of preparing a cellulose acylate film from the cellulose acylate solution.

A metal substrate (casting belt) of stainless steel having a width of 2 m and a length of 56 m (area 112 m ² ) was used. The metal substrate had an arithmetic average roughness (Ra) of 0.006 μm, a maximum height (Ry) of 0.06 μm, and a ten-point average roughness (Rz) of 0.009 μm. Arithmetic mean roughness (Ra), maximum height (Ry) and ten-point mean roughness (Rz) were measured in accordance with JIS B0601.

Immediately after casting, the casting coating dope was dried with an air velocity of 0.5 m/sec or less for 1 second, and then dried with an air velocity of 15 m/sec. The temperature of the drying air was 50°C.

The residual solvent content of the film peeled from the casting tape was 230% by weight, and the temperature was -6°C. The average drying rate from casting to peeling was 744%/min, and the gelling temperature of the coating dope at the time of peeling was about 10°C.

The film was dried for 1 minute after the surface temperature of the film on the metal substrate reached 40°C, and then peeled off, and the temperature of the drying air was changed to 120°C. In this state, the temperature distribution of the film in the transverse direction is 5°C or less, the average velocity of the dry air is 5m/sec, the heat transfer coefficient is 25kcal/m ² ·Hr·°C on average, and the film has a temperature of 5% in the transverse direction. The distribution of these values within . In the drying zone, the film part carried by the tenter needles is blocked by the air to avoid the drying hot air.

A process of stretching the cellulose acylate film is then performed. In the state of a film with a residual solvent amount of 15% by weight, the film was stretched transversely at 130°C at a stretching coefficient of 25% via a tenter, then kept at this stretched width at 50°C for 30 seconds, and then removed from the stretcher. Release on the frame clips and wind into a roll. The solvent evaporation from peeling to rolling up corresponds to 97% by weight of the solvent originally used. The dried film was then dried with dry air at 145° C. in the drying step under roller transport, and then subjected to temperature and humidity adjustment and rolled up at a residual solvent amount of 0.32% by weight and a moisture content of 0.8% by weight, thereby obtaining fibers Urocylate film (CA-1) (length 3500 m, width 1300 mm, thickness 80 µm, refractive index 1.48). It showed a thickness fluctuation of ±2.4%, and the curl value in the transverse direction was -0.2/m.

[Surface Irregularity of Film]

Table 34 shows the results of measuring the surface irregularities on the belt-side surface of the obtained cellulose acylate film. Table 34 also shows the evaluation results of the following optical characteristics and mechanical properties.

(Optical properties of thin films)

(haze)

Haze was measured with a haze meter (Model 1001DP, manufactured by Nippon Denshoku Kogyo Co.). Measurements were made at 5 points on each film sample and the average value calculated.

[Evaluation of Mechanical Properties]

(curly)

The curl value was determined according to the test method defined by the American National Standards Institute (ANSI/ASCPH 1.29-1985, Method-A). The polymer film was cut into a size of 35 mm in width and 2 mm in length, and fixed on a curling plate. The curl value after humidity conditioning for 1 hour in an environment of 25° C. and 65% RH was read. Similarly, a polymer film was cut into a size of 2 mm in width and 35 mm in length and fixed on a curling plate. The curl value after humidity conditioning for 1 hour in an environment of 25° C. and 65% RH was read. The measurement was carried out in the transverse direction and the longitudinal direction, and the larger value was taken as the curl value. The curl value is represented by the reciprocal of the radius of curvature (m).

(tear strength)

The film was cut into a size of 65mm wide and 50mm long to make a sample, and then it was subjected to humidity conditioning in a room with a temperature of 30°C and a relative humidity of 85%, and a light load tear strength tester manufactured by Tokyo Seiki Mfg.Co. in accordance with ISO6383 The standard of /2-1983 is determined by the load (g) required for tearing.

[Film Properties]

(optical defect)

The film was cut into a size of 1300 mm in width and 5 m in length to prepare a sample. Brightness defects were counted under naked eye observation with two polarizers placed in crossed Nicols and the sample placed between them. The number of bright spots with a size of 100 μm or larger is counted and expressed in number per meter.

(moisture permeability)

Measured under the conditions of a temperature of 25°C and a humidity of 90%RH according to the method defined in JIS Z0208, and the result is converted into a film thickness of 80μm.

Table 34 film number Film thickness (μm) Thickness change (%) curly Ra(μm) Rz(μm) Haze (%) Tear strength (g) Moisture permeability ^* optical defect CA-1 80 ±2.4 -0.2/m 0.005 0.015 0.3 12 885 0.2

Permeability ^* : converted to 80μm (unit: g/m ² ·24h)

[Preparation of anti-reflection film (AF-4)]

On the aforementioned cellulose acylate film (CA-1), Pelnox C-4456-S7 (trade name of ATO-dispersed hard coat agent, solid: 45%, manufactured by Nippon Pelnox Ltd.) was coated, and dried by ultraviolet irradiation hardened to form a conductive layer with a thickness of 1 μm. The film had a surface resistivity of about 10 ⁸ Ω/sq.

After the sample was left to stand under the condition of 25°C/65%RH for 1 hour, the surface resistivity was measured with a resistivity meter MCP-HT260 manufactured by Mitsubishi Chemical Corp.

(Coating solution for anti-glare hard coat)

50 parts by weight of a pentaerythritol triacrylate/pentaerythritol tetraacrylate mixture (Peta, manufactured by Nippon Kayaku Co.), 2 parts by weight of a curing initiator (Irgacure 184, manufactured by Ciba-Geigy Inc.), 5 parts by weight of propylene Acyl-styrene beads (manufactured by Soken Chemical and Engineering Co., particle diameter: 3.5 μm, refractive index: 1.55) as the first translucent particles, 5.2 parts by weight of styrene beads (manufactured by Soken Chemical and Engineering Co., particle diameter : 3.5 μm, refractive index: 1.60) as the second translucent particles, 10 parts by weight of the silane coupling agent KBM-5103 (manufactured by Shin-Etsu Chemical Co.) and 0.03 parts by weight of the following fluoropolymer (PF- 2) Mix with 50 parts by weight of toluene to obtain a coating liquid. The aforementioned cellulose acylate film having a conductive layer was unwound from a roll and coated with the coating liquid to obtain a dry film thickness of 6.0 μm, and after evaporation of the solvent, was heated with a 160 W/cm air-cooled metal halide lamp ( (manufactured by Eyegraphics Co.)) was irradiated with ultraviolet light at an irradiation intensity of 400 mW/cm ² and an irradiation amount of 300 mJ/cm ² to harden the coating, thereby obtaining an anti-glare hard coat layer (refractive index 1.62).

Fluoropolymer (PF-2)

Mw: 3×10 ⁴ (calculated by molar composition ratio)

(Preparation of anti-reflection film (AF-4))

On this anti-glare layer, the coating liquid of the low-refractive-index layer (AL-1) was apply|coated with the gravure coater. After drying at 80°C, with an air-cooled metal halide lamp of 160 W/cm (manufactured by Eyegraphics Co.) in an atmosphere having an oxygen concentration of 1.0% by volume or less under nitrogen flushing at an irradiation intensity of 550 mW/cm and ^irradiating It was irradiated with ultraviolet light in an amount of 600 mJ/cm ² to obtain a low refractive index layer (refractive index: 1.43, film thickness: 86 nm). In this way, an antireflection film (AF-4) of the present invention was produced. The obtained antireflection film had an average reflectance of 2.1% and a haze of 43%.

Properties as described in Example D-1 with respect to mechanical properties and durability were evaluated in the same manner as in Example D-1. Also, the sharpness and the uniformity of the color tone of the reflected light were as satisfactory as those of the antireflection film of Example D-1.

(surface treatment)

Heat 2.0 mol/L sodium hydroxide aqueous solution to 55°C, and soak the anti-reflection film (AF-4) in it for 2 minutes, then fully rinse with water and dry, so that the cellulose acyl film opposite to the anti-reflection film A hydrophilic surface is formed on the compound film.

[Optical Compensation Sheet]

On the surface of the cellulose acylate film (CA-1), a 1.0 mol/L potassium hydroxide aqueous solution was coated with a #3 bar, and then, after being treated at a film surface temperature of 60° C. for 10 seconds, rinsed with water and dried . The obtained film had a surface showing a contact angle with water of 35° and a surface energy of 66 mN/m.

[Preparation of Oriented Film]

On the thus surface-treated film, the coating liquid of the oriented film of ^{the following} composition was coated with a coating amount of 28 mL/m by a bar coater, and dried by dry air at 60° C. for 60 seconds, and then passed through 90 C in dry air for 150 seconds.

Coating solution for oriented film:

The following denatured polyvinyl alcohol 20 parts by weight

Citric acid 0.05 parts by weight

Glutaraldehyde 0.5 parts by weight

Water 360 parts by weight

Methanol 120 parts by weight

denatured polyvinyl alcohol

(Rubbing of oriented film)

Rubbing treatment was performed on the surface of the oriented film by passing a rubbing roll on which a commercially available rubbing cloth was used in the longitudinal direction of the film and parallel to the conveying direction under an ambient condition of 25° C./45% RH.

(Formation of optically anisotropic layer)

On this oriented film, use #3.4 wire-wound bar to coat the trimethylolpropane triacrylate which is denatured by 41.01 parts by weight of the discotic liquid crystal compound (DA) of the following structure and 4.06 parts by weight of ethylene oxide. (V#360, manufactured by Osaka Organic Chemical Industries, Ltd.), 0.90 parts by weight of cellulose acetate butyrate (CAB551-0.2, manufactured by Eastman Chemical Ltd.), 0.23 parts by weight of cellulose acetate butyrate (CAB531-1 , manufactured by Eastman Chemical Ltd.), 1.35 parts by weight of photopolymerization initiator (Irgacure907, manufactured by Ciba-Geigy Ltd.), 0.45 parts by weight of sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co.) and 0.40 parts by weight A coating liquid in which 102 parts by weight of a fluorinated surfactant (PF-3) of the following structure was dissolved in 102 parts by weight of methyl ethyl ketone. The discotic liquid crystal compound was oriented by heating in a constant temperature zone at 130°C for 2 minutes, and then polymerized by ultraviolet irradiation for 1 minute in an atmosphere of 60°C with a high-pressure mercury lamp of 120 W/cm. Then cool by standing to room temperature. In this way, an optically anisotropic layer having a thickness of 2.0 µm was produced, whereby an optical compensation sheet (WV-1) was obtained.

Discotic liquid crystal compound (DA)

Fluorinated Surfactant (PF-3): C ₈ F ₁₇ CH ₂ CH ₂ O(CH ₂ CH ₂ O) ₁₀ H

(surface treatment)

In a similar manner to the saponification process of the surface of the antireflection film, the film surface of the obtained optical compensation sheet opposite to the optically anisotropic layer was subjected to a saponification process.

[Polarizing sheet (H-2) and viewing side polarizing sheet (SHB-4)]

A PVA film with an average degree of polymerization of 2,400 and a thickness of 75 nm was pre-swelled in ion-exchanged water at 40°C for 60 seconds, and then, after the moisture on the surface was scraped off with a stainless steel blade, the concentration was adjusted to maintain a constant concentration. Soak in an aqueous solution containing 0.7g/L iodine, 60.0g/L potassium iodide and 1g/L boric acid at 40°C for 55 seconds, then adjust the concentration to maintain a constant concentration in an aqueous solution containing 42.5g/L boric acid, 30g/L Potassium iodide, 0.1g/LC.I. Direct Yellow 44 (λmax 410nm) and 0.1g/L C.I. Direct Blue 1 (λmax 650nm) in an aqueous solution soaked at 40°C for 90 seconds, and scraped off two After excess liquid on the surface, it is fed into a tenter for transverse uniaxial stretching. After stretching 100 m of this film by 4.12 times at a transport speed of 4 m/min in an atmosphere of 60° C. and 95% RH, the film was kept at a constant width, and the film was dried while shrinking in an atmosphere of 65° C. It was removed from the tenter to obtain a polarizing sheet (H-2). The polarizing sheet (H-2) had a thickness of 17.5 μm and a moisture content of 3% by weight.

Then, after cutting off the lateral side by 3 cm with a cutter, an aqueous solution of 3% PVA (PVA-124H, manufactured by Kuraray Co.) was used as an adhesive to bond it with the saponified surface of the antireflection film (AF-4) and The saponified surface of the saponified optical compensation sheet was adhered and heated at 70° C. for 10 minutes to obtain a viewing side polarizing plate (SHB-4) having an effective width of 650 mm and a length of 100 m.

[Liquid crystal display device]

In a 20-inch IPS mode liquid crystal display device (W20-1c3000, manufactured by Hitachi Ltd.), the optical film provided therein was replaced with a polarizing plate (SHB-4) in such a manner that the optically anisotropic layer was located on the liquid crystal cell side Adhere on viewing side with acrylic adhesive. Also on the back side, a polarizing plate (BHB-1) was attached with an acrylic adhesive in such a manner that the transparent protective film of the polarizing plate was on the liquid crystal cell side.

[Image display performance of liquid crystal display device]

The image quality of the image displayed on the display device of Example D-14 was evaluated in a similar manner to Example D-11. As a result, a satisfactory uniform image without glare was obtained, and the black display tone, contrast, viewing angle and tone neutrality were satisfactory.

Example D-15

[Polarizing sheet (H-3) and viewing side polarizing sheet (SHB-5)]

Observation-side polarizer (SHB-5) was prepared in the same manner as the observation-side polarizer (SHB-1) of Example D-11, except that the polarizing sheet (H-1) was replaced with the following polarizing sheet (H-3) .

(Polarizing sheet H-3)

A PVA film with an average degree of polymerization of 2,400 and a thickness of 75 nm was pre-swelled in ion-exchanged water at 40°C for 60 seconds, and then, after the moisture on the surface was scraped off with a stainless steel blade, the concentration was adjusted to maintain a constant concentration. Soak in an aqueous solution containing 0.7g/L iodine, 60.0g/L potassium iodide and 1g/L boric acid at 40°C for 55 seconds, then adjust the concentration to maintain a constant concentration in an aqueous solution containing 42.5g/L boric acid and 30g/L It was soaked in an aqueous solution of potassium iodide at 40° C. for 90 seconds, and after scraping off excess liquid on both surfaces with a stainless steel blade, was charged into a tenter of the shape shown in FIG. 1 . After stretching 100 m of this film 4.5 times in an atmosphere of 60° C. and 95% RH at a conveying speed of 4 m/min, the tenter was bent with respect to the stretching direction shown in FIG. 1 , and then the width was kept constant. The film was dried while shrinking in an atmosphere of 65° C. and removed from the tenter to obtain a polarizing sheet (H-3). The polarizing sheet (H-3) had a thickness of 16 μm and a moisture content of 3% by weight.

During the stretching operation for preparing the antireflection film, the temperature was kept within a variation range of 60±0.1° C. and the humidity was kept within a range of 95±0.5%. The PVA film had a moisture content of 33% by volume before starting stretching, and a moisture content of 3% by weight after drying.

The difference between the transport speeds of the tenter clips (clamps) on the left and right sides of the PVA film is less than 0.05%, and the centerline of the added film and the centerline of the film advancing to the next step form an angle of 47°. The condition that |L1-L2| is 0.7m and W is 0.7m is maintained such that |L1-L2|=W. The approximate stretching direction Ax-Cx at the tenter exit is inclined at 45° relative to the center line 22 of the film advancing to the next step. At the exit of the tenter frame, shrinkage and film deformation were not observed.

The obtained polarizing plate had an absorption axis inclined at 45° to the longitudinal direction.

[Liquid crystal display device]

In a 22-inch VA-mode liquid crystal display device (TH22-LH10, manufactured by Matsushita Electric Co.), the polarizing plate on the viewing side was replaced with the aforementioned polarizing plate (SHB-5) with an optically anisotropic layer on the liquid crystal cell side. way attached to the viewing side with an acrylic adhesive.

The properties of the polarizing plate and display device thus obtained were evaluated in the same manner as in Example D-1. The results were satisfactory as in Example D-1.

Example C-16

In the polarizing plate (P-1) having an antireflection film on one side prepared in Example C-1, the transparent protective film opposite to the antireflection film was adhered to a λ/4 plate, and adhered to an organic EL display The front glass panel of the device. As a result, reflections on the glass surface and from inside the glass plate are suppressed, and an extremely high-visibility display with a neutral tone can be obtained.

<Embodiment E>

[Example E-1]

<Preparation of substrate>

(Preparation of Particle Dispersion (RL-1))

A mixture of the following components and zirconia beads having a diameter of 0.2 mm was wet dispersed in a bead mill to obtain a volume average particle diameter of 55 nm. The beads were separated from the obtained dispersion with a 200-mesh nylon cloth to obtain a particle dispersion (RL-1).

The particle size distribution determined for the obtained particle dispersion confirmed that particles having a size of 300 nm or larger accounted for 0%.

The volume average particle diameter is measured with a particle size distribution measuring apparatus LA920 (manufactured by Horiba Mfg. Co.).

*The composition of particle dispersion (RL-1):

Hydrophobic silica (Aerosil R812, methyl-modified, primary particle size: 2.00 parts by weight

7nm, manufactured by Nippon Aerosil Co.)

Cellulose triacetate (degree of substitution: 2.85, 6-position substitution: 0.90) 2.00 parts by weight

The following dispersant (DP-2) 0.25 parts by weight

Dichloromethane 78.70 parts by weight

Methanol 14.20 parts by weight

1-butanol 2.86 parts by weight

Dispersant (DP-2)

(Preparation of Cellulose Acylate Solution (A-1))

The mixture composed below was stirred and dissolved to obtain a cellulose acylate solution (A-1).

^* Composition of Cellulose Acylate Solution (A-1)

Cellulose triacetate with a degree of substitution of 2.85 (6-position substitution: 0.90) 89.3 parts by weight

Triphenyl phosphate (logP 5.60) 7.1 parts by weight

Biphenyl diphenyl phosphate (logP 7.28) 3.6 parts by weight

The following ultraviolet absorber: UV-E1 0.5 parts by weight

The following ultraviolet absorber: UV-E2 0.7 parts by weight

The following ultraviolet absorber: UV-E3 0.8 parts by weight

Dichloromethane 300 parts by weight

Methanol 54 parts by weight

1-butanol 11 parts by weight

x R ¹ R ² UV-E1: UV-E2: UV-E3: -Cl-Cl-H -C ₄ H ₉ (t) -C ₄ H ₉ (t) -C ₁₂ H ₂₅ -CH ₃ -(CH ₂ ) ₂ COOC ₈ H ₁₇ -CH ₃

(Preparation of Coating Dope)

In 474 parts by weight of cellulose acylate solution (A-1), 15.3 parts by weight of particle dispersion (RL-1) was added under stirring, and then the mixture was stirred well, and left to stand at room temperature (25° C.) 3 hours, and the obtained heterogeneous gel-like solution was cooled at -70°C for 6 hours, heated and stirred at 50°C to obtain a completely dissolved coating dope.

The obtained coating dope was filtered at 50° C. with a filter paper (#63, manufactured by Toyo Filtering Paper Co.) with an absolute filtration accuracy of 0.01 mm, and then with a filter paper with an absolute filtration accuracy of 0.0025 mm (FH025, manufactured by Pall Inc. production) to filter and remove air bubbles to obtain a coating dope.

(solution casting process)

After the aforementioned preparation of the cellulose acylate solution, the coating dope thus obtained was cast with a belt caster used in the process of preparing a cellulose acylate film from the cellulose acylate solution.

A metal substrate (casting belt) of stainless steel having a width of 2 m and a length of 56 m (area 112 m ² ) was used. The metal substrate had an arithmetic average roughness (Ra) of 0.006 μm, a maximum height (Ry) of 0.06 μm, and a ten-point average roughness (Rz) of 0.009 μm. Arithmetic mean roughness (Ra), maximum height (Ry) and ten-point mean roughness (Rz) were measured in accordance with JIS B0601.

Immediately after casting, the casting coating dope was dried with an air velocity of 0.5 m/s or less for 1 second, and then dried with an air velocity of 15 m/s. The temperature of the drying air was 50°C.

The residual solvent content of the film peeled from the casting tape was 230% by weight, and the temperature was -6°C. The average drying rate from casting to peeling was 744%/min, and the gelling temperature of the coating dope at the time of peeling was about 10°C.

The film was dried for 1 minute after the surface temperature of the film on the metal substrate reached 40°C, and then peeled off, and the temperature of the drying air was changed to 120°C. In this state, the temperature distribution of the film in the transverse direction is 5°C or less, the average velocity of the dry air is 5m/s, the heat transfer coefficient is 25kcal/m ² ·Hr·°C on average, and the film has a temperature distribution of 5% in the transverse direction. The distribution of these values within . In the drying zone, the film part carried by the tenter needles is blocked by the air to avoid the drying hot air.

A process of stretching the cellulose acylate film is then performed. In the state of a film with a residual solvent amount of 15% by weight, the film was stretched transversely at 130°C at a stretching coefficient of 25% via a tenter, then kept at this stretched width at 50°C for 30 seconds, and then removed from the stretcher. Release on the frame clips and wind into a roll. The solvent evaporation from peeling to rolling up corresponds to 97% by weight of the solvent originally used. The dried film was then dried with dry air at 145° C. in the drying step under roller transport, and then subjected to temperature and humidity adjustment and rolled up at a residual solvent amount of 0.35% by weight and a moisture content of 0.8% by weight, thereby obtaining fibers A monocylate film (CA-1) (length 3500 m, width 1300 mm, thickness 80 µm, refractive index 1.48) was used as a transparent substrate. It showed a thickness fluctuation of ±2.4%, and the curl value in the transverse direction was 0.2/m.

[Surface Irregularity of Film]

The surface irregularities on the surface of the obtained cellulose acylate film sample CA-1 on the tape side were measured, and the results are shown in Table 35. Table 35 also shows the evaluation results of the following optical characteristics and mechanical properties.

(Optical properties of thin films)

* Haze

Haze was measured with a haze meter (Model 1001DP, manufactured by Nippon Denshoku Kogyo Co.). Measurements were made at 5 points on each film sample and the average value calculated.

(evaluation of mechanical properties)

^* curl

The curl value was determined according to the test method defined by the American National Standards Institute (ANSI/ASCPH 1.29-1985, Method-A). The polymer film was cut into a size of 35 mm in width and 2 mm in length, and fixed on a curling plate. The curl value after humidity conditioning for 1 hour in an environment of 25° C. and 65% RH was read. Similarly, a polymer film was cut into a size of 2 mm in width and 35 mm in length and fixed on a curling plate. The curl value after humidity conditioning for 1 hour in an environment of 25° C. and 65% RH was read. The measurement was carried out in the transverse direction and the longitudinal direction, and the larger value was taken as the curl value. The curl value is represented by the reciprocal of the radius of curvature (m).

^* Tear strength

The film was cut into a size of 65mm wide and 50mm long to make a sample, and then it was subjected to humidity conditioning in a room with a temperature of 30°C and a relative humidity of 85%, and a light load tear strength tester manufactured by Tokyo Seiki Mfg.Co. in accordance with ISO6383 The standard of /2-1983 is determined by the load (g) required for tearing.

(film properties)

^* Optical defects

Two polarizers were placed in crossed Nicols position, and a sample with a width of 1300 mm and a length of 5 m was placed between them, and brightness defects were counted under naked eye observation. The number of bright spots with a size of 100 μm or larger is counted and expressed in number per meter.

^* Moisture permeability

Measured under the conditions of temperature 25°C and humidity 90%RH according to the method defined in JIS Z0208.

Table 35 film number Film thickness (μm) Thickness change (%) Ra(μm) Rz(μm) Haze (%) Curl/m Tear strength (g) optical defect Moisture permeability ^* CA-1 80 ±2.5 0.005 0.015 0.3 0.2/m 12 0.2 250

<Preparation of anti-reflection film (AF-1)>

(Preparation of coating solution for hard coat layer)

750.0 parts by weight of trimethylolpropane triacrylate (TMPTA, manufactured by Nippon Kayaku Co.), 270.0 parts by weight of poly(glycidyl methacrylate) with a weight average molecular weight of 3,000, 730.0 parts by weight of methyl Ethyl ketone, 500.0 parts by weight of cyclohexanone and 50.0 parts by weight of a photopolymerization initiator (Irgacure 184, manufactured by NipponCiba-Geigy Ltd.), were stirred, and filtered through a polypropylene filter with a pore size of 0.4 μm to obtain hard Coating fluid.

(Preparation of Titanium Dioxide Particle Dispersion A)

As the titanium dioxide particles, titanium dioxide particles containing cobalt and subjected to surface treatment of aluminum hydroxide and zirconium hydroxide (MPT-129C, manufactured by Ishihara Sangyo Co.) were used.

To 257.1 parts by weight of these particles, 38.6 parts by weight of the following dispersant and 704.3 parts by weight of cyclohexanone were added and dispersed in a bead mill to obtain a titanium dioxide dispersion A having a weight average particle diameter of 70 nm.

Dispersant

Mw: 1.5×10 ⁴ (calculated by molar composition ratio)

(Preparation of Coating Liquid for Middle Refractive Index Layer)

88.9 parts by weight of the aforementioned titanium dioxide dispersion A, a mixture of 58.4 parts by weight of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA), 3.1 parts by weight of a photopolymerization initiator (Irgacure 907), 1.1 parts by weight of photopolymerization A sensitizer (KayacureDETX, manufactured by Nippon Kayaku Co.), 482.4 parts by weight of methyl ethyl ketone and 1869.8 parts by weight of cyclohexanone were stirred, and filtered through a polypropylene filter with a pore size of 0.4 μm to obtain a medium refractive index layer of coating solution.

(Preparation of Coating Liquid for High Refractive Index Layer)

586.8 parts by weight of the aforementioned titanium dioxide dispersion, 47.9 parts by weight of DPHA, 4.0 parts by weight of Irgacure 907, 1.3 parts by weight of Kayacure DETX, 455.8 parts by weight of methyl ethyl ketone and 1427.8 parts by weight of cyclohexanone were stirred, and It was filtered through a polypropylene filter with a pore diameter of 0.4 μm to obtain a coating liquid for a high refractive index layer.

(Preparation of Coating Liquid for Low Refractive Index Layer)

1.4 parts by weight of DPHA, 5.6 parts by weight of fluoropolymer (PF-1) of the following structure, 20.0 parts by weight of hollow silica (average particle diameter: 40nm, shell thickness: 7nm, refractive index: 1.31, iso 18% by weight in propanol) as hollow particles, 0.7 parts by weight of reactive polysiloxane "RMS-033" (manufactured by Gelest Inc.), 6.2 parts by weight of the following sol liquid a, 0.2 parts by weight of Irgacure 907 and 315.9 Parts by weight of methyl ethyl ketone were stirred and filtered through a polypropylene filter with a pore size of 1 μm to obtain a coating solution for the low refractive index layer.

Fluoropolymer (PF-1)

Mw: 5×10 ⁴ (molar composition ratio)

(Preparation of sol liquid a)

In a reactor equipped with a stirrer and a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co.) It was mixed with 3 parts of ethyl diisopropylaluminum acetoacetate, and then 30 parts of ion-exchanged water was added, and the mixture was reacted at 60° C. for 4 hours and cooled to room temperature to obtain a sol liquid. Its weight-average molecular weight is 1,600, and among components equal to or greater than oligomers, components with a molecular weight of 1,000-20,000 account for 100%. Furthermore, gas chromatographic analysis revealed that no acryloxypropyltrimethoxysilane used as a raw material remained at all.

(Preparation of anti-reflection film (AF-1))

On the aforementioned cellulose triacetate film in the form of a roll, the coating solution for the hard coat layer was coated with a gravure coater. After drying at 100° C., an air-cooled metal halide lamp (manufactured by Eyegraphics Co.) of 160 W/cm was used at an irradiation intensity of 400 mW/cm ² and an irradiation amount of It was irradiated with ultraviolet light of 300 mJ/cm ² to harden the coating, thereby obtaining a hard coating layer having a thickness of 8 μm.

On the obtained hard coat layer, a coating liquid for a medium refractive index layer and a coating liquid for a high refractive index layer were successively coated with a gravure coater having three coating points.

The drying condition of the middle refractive index layer was 2 minutes at 100° C., and the ultraviolet curing condition was: irradiation intensity 400 mJ/cm ² and irradiation amount 400 mW/cm ² , using a 180 W/cm air-cooled metal halide lamp (manufactured by Eyegraphics Co. ), an oxygen concentration of 1.0% by volume or less was obtained under nitrogen flushing. The medium index layer had a refractive index of 1.630 and a thickness of 67 nm after curing.

The drying conditions of the high refractive index layer are 1 minute at 90°C and 1 minute at 100°C, and the ultraviolet curing conditions are: irradiation intensity 600mJ/cm ² and irradiation amount 600mJ/cm ² , using a 240W/cm air-cooled metal halide lamp (manufactured by Eyegraphics Co.), an oxygen concentration of 1.0% by volume or less was obtained under nitrogen flushing. The high refractive index layer had a refractive index of 1.905 and a thickness of 107 nm after curing.

On the high refractive index layer, using a microgravure roll with a diameter of 50 mm and a doctor blade with a gravure pattern with a line count of 180 lines/inch and a depth of 40 μm, at a rotation speed of the gravure roll of 30 rpm and a transport speed of 15 m/min The coating solution for the low-refractive index layer was down-coated, then dried at 120° C. for 150 seconds, and then dried at 140° C. for 8 minutes, and heated with a 240 W/cm air-cooled metal halide lamp (manufactured by Eyegraphics Co.) Under nitrogen flushing, irradiate with ultraviolet light with an irradiation intensity of 400mW/ ^cm2 and an irradiation amount of 900mJ/ ^cm2 to form a low refractive index layer (AL-1) with a thickness of 100nm, thereby obtaining an antireflection film (AF-1).

[Comparative Examples E1-1 to E1-3]

Antireflection films (AFR-1)-(AFR-3) of Comparative Examples E1-1 to E1-3 were prepared in the same manner as in Example E-1 except that Example E-1 was changed as shown in Table 36 The average particle diameter and shell thickness of the hollow particles in the low-refractive index layer in the antireflection film (AF-1) of the above-mentioned anti-reflection film (AF-1) to maintain substantially the same refractive index as the hollow silica of Example E-1.

Table 36 Anti-reflection film low refractive index layer Hollow Particle Size/Shell Thickness Thickness of low refractive index layer Thickness ratio of hollow particles The refractive index of the low refractive index layer Example E-1 AF-1 AL-1 40nm/7nm 100nm 40% 1.43 Comparative Example E1-1 AFR-1 ALR-1 none 100nm - 1.46 Comparative Example E1-2 AFR-2 ALR-2 25nm/4nm 100nm 25% 1.43 Comparative Example E1-3 AFR-3 ALR-3 105nm/18nm 100nm 105% 1.43

(Evaluation of anti-reflection film)

The following properties of each of the antireflection films of Example E-1 and Comparative Examples E1-1 to E1-3 were evaluated, and the results are shown in Table 37. Haze was evaluated in a similar manner to the cellulose acylate film.

(1) Pencil hardness test

As an index of scratch resistance, pencil hardness was evaluated according to JIS K-5400. The polarizing plate with the antireflection film was conditioned at a temperature of 25°C and a humidity of 60%RH for 2 hours, and measured at 5 points on the surface of the antireflection film under a load of 1 kg with a 3H measuring pencil defined in JIS S-6006, Visually evaluate the results according to the following levels:

A: No scratches were observed at all points;

B: 1 or 2 scratches;

C: 3 or more scratches.

(2) Surface energy

As an index of surface stain resistance (fingerprint resistance), the surface energy of the samples was determined in the aforementioned manner after conditioning the samples at 25° C. and 60% RH for 2 hours.

(3) Dynamic friction coefficient

The surface lubricity was evaluated using the coefficient of kinetic friction. After the sample was conditioned at 25° C. and 60% RH for 2 hours, dynamic friction was measured with a dynamic friction meter Heidon-14 (manufactured by Shinto Kagaku Co.) using a stainless steel ball with a diameter of 5 mm under a load of 100 g and a speed of 60 cm/min. coefficient.

(4) Adhesive properties

The antireflection film was subjected to humidity conditioning for 2 hours under the conditions of temperature 25°C and humidity 60%RH. Then, on the surface of the light-diffusing layer of the antireflection film, cut eleven notches in the longitudinal and transverse directions with a cutter to form 100 squares, and then glue them with a polyester adhesive tape (No.31B, manufactured by Nitto) at the same position. Denko Co.) adhesion test was repeated 3 times, and the degree of peeling was visually observed and evaluated in the following four levels:

AA: No peeling was observed in all 100 squares;

A: Peeling was observed in 2 or less of 100 squares;

B: Peeling was observed in 3-10 out of 100 squares;

C: Peeling was observed in more than 10 out of 100 squares.

(5) Steel wool scratch resistance

On the antireflection film before and after exposure, after moving #0000 steel wool for 60 reciprocating cycles with a load of 500 g/cm ² , scratches were visually observed and evaluated in the following three levels:

A: No scratches at all;

B: The scratches formed are not easy to see;

C: Scratches are conspicuous.

(6) Tone uniformity

With a spectrophotometer V-550 (manufactured by JASCO Corp.) equipped with an adapter ARV-474, the specular reflectance was measured at an incident angle of 5°, an output angle of -5° in the wavelength range of 380-780 nm, and then used The reflection spectrum measured in the wavelength range of 450-650nm, calculate the L ^* value, a ^* and b ^* value of the CIE1976L ^* a ^* b ^* color space representing the color tone of the normal reflected light at the 5° incident angle of the CIE standard light source D65 , and evaluate the hue of reflected light by a ^* and b ^* values.

A film having a length of 1 m was used as a sample, and measurements were performed at three points at the center of the roll and at both ends in the longitudinal and transverse directions. Samples were taken from the front portion, center portion and tail portion of the applicator roll. Each value represents the central value of these measurement points, and the rate of change was obtained by dividing the difference between the maximum value and the minimum value by the central value and expressed in %. Evaluate according to the following four levels:

A: The rate of change is 10% or less;

B: The rate of change is greater than 10% but less than 20%;

C: The rate of change is 21% or more.

(7) Weather resistance

The weathering test was carried out using a sunlight weathering tester (S-80, manufactured by Suga Shiken-ki Co.) at a humidity of 50% for an exposure time of 200 hours.

(Determination of reflectance and reflectance spectrum)

On the samples before and after the weathering test, measure the specular reflectance and reflection spectrum of the incident light at an incident angle of 5° in the same manner as the measurement of the specular reflectance, and calculate the reflectance in the wavelength range of 380-780nm and the hue of reflected light on the CIE chromaticity diagram to determine the change in average reflectance and hue between before and after the weathering test, and evaluate at the following four levels:

(Change in hue ΔE in reflected light)

AA: ΔE is 5 or less;

A: ΔE is 5-10;

B: ΔE is 10-15;

C: ΔE is 15 or more.

(8) Clarity

Visually observe the inhomogeneity of transmitted light from a sample placed between two crossed Nicols polarizers:

A: There is no inhomogeneity at all (no recognition among the 10 discriminators);

B: slightly non-uniform (identified by 1-5 out of 10 discriminators);

C: Unevenness is strongly generated (identified by 6 or more out of 10 discriminators).

Table 37 Haze (%)/Reflectance (%) pencil hardness surface energy dynamic friction coefficient adhesiveness Scratch resistance Uniformity of tone weather resistance clarity Example E1 0.31/0.40 A 25mN/m 0.12 A A A AAA A Comparative Example E1-1 0.31/0.56 A 25mN/m 0.12 C B A B A Comparative Example E1-2 0.30/0.49 B 25mN/m 0.12 A C B C A Comparative Example E1-3 0.39/0.42 C 26mN/m 0.21 C C C C B

Example E-1 corresponding to the invention shows low reflectivity and excellent mechanical properties of the film. Also, the displayed image exhibited excellent sharpness and almost neutral tone. Furthermore, the properties after the weathering test were satisfactory. Comparative Example E1-1 was inferior in adhesiveness, scratch resistance and image clarity. Comparative Example E1-2 was inferior in film strength, image clarity and color tone. Comparative Examples E1-3 were deficient in adhesiveness, film strength, image display properties (sharpness and color tone) and weather resistance.

(Antireflective Polarizer (Upper Polarizer))

Aforesaid antireflection film, on the surface of the cellulose acylate film opposite to antireflection layer, pass through saponification process by coating saponification solution, this saponification solution is made of potassium hydroxide of 57 parts by weight, propylene glycol of 120 parts by weight, 535 An alkaline solution is composed of isopropanol in parts by weight and water in 288 parts by weight and maintained at 40°C.

The alkali solution on the saponified surface of the substrate is fully rinsed off with water, and fully dried at 100°C.

Iodine adsorption was performed by soaking a polyvinyl alcohol film (manufactured by Kuraray Co.) having a thickness of 75 μm in an aqueous solution consisting of 1000 g of water, 7 g of iodine, and 105 g of potassium iodide for 5 minutes. Then, the film was uniaxially stretched 4.4 times in the longitudinal direction in a 4% by weight aqueous solution of boric acid, and dried in the stretched state to obtain a polarizing sheet.

Using a polyvinyl alcohol-based adhesive, the surface of the polarizing sheet was adhered to the saponified cellulose acylate surface of the antireflection film (surface protective film for polarizing plate AF-1). Also, the other surface of the polarizing sheet was adhered to a similarly saponified cellulose acylate film (CA-1) using the same polyvinyl alcohol-based adhesive.

(Antireflective Polarizer with Optical Compensation (Observation Side Polarizer/Top Polarizer))

An optical compensation film (wide field of view film A 12B manufactured by FujiPhoto Film Co.) with an optical compensation layer, wherein the disk of the disk-shaped structural unit is inclined towards the surface of the substrate, and the disk-shaped surface of the disk-shaped structural unit and the surface of the substrate The angle between the surfaces varies with the depth of the optically anisotropic layer, and on the substrate surface of the optically compensating film opposite to the optically compensating layer, a saponification process is performed under conditions similar to those described above.

The surface of the cellulose triacetate film opposite to the antireflection film of the aforementioned polarizing plate having the antireflection film was similarly subjected to alkali saponification.

The saponified cellulose triacetate film surface of the optical compensation film and the polarizing plate with the antireflection film were bonded to each other using a polyvinyl alcohol-based adhesive, whereby a viewing side polarizing plate (SHB-1) was produced.

(back polarizer)

One side of the cellulose acylate film (CA-1) was subjected to the alkali saponification treatment as explained above, and it was adhered to the same polarizing sheet as the polarizing sheet prepared in the polarizing plate with a polyvinyl alcohol-based adhesive. As protective films on both sides, a polarizing plate was obtained.

Then, on the surface of the polarizing plate thus prepared, a light-diffusing adhesive substance (refractive index 1.47) was adhered to a thickness of 25 μm. This light-diffusing adhesive is prepared by adding silica particles (particle diameter: 4 μm, refractive index: 1.44) to an acrylic adhesive (refractive index: 1.47) at 50% by weight and forming a film, corresponding to haze for 88. Then, a brightness improving film PCF400 (a base material of a PET film having a thickness of 50 μm and a total thickness of about 53 μm; manufactured by Nitto Denko Co.) was bonded. The light concentrating film was then produced by evaporating the film, a laminate of 15 layers of TiO ₂ /SiO ₂ . The light concentrating film corresponds to the emission spectra of cold cathode tubes at 435, 545 and 610 nm and has the property of focusing these lights into a frontal range of ±45°.

On the surface of the polarizing plate on the side of the cellulose acylate film (CA-1) opposite to the brightness improving film, and the substrate surface of the optical compensation film wide field of view A12B, saponification treatment was carried out by coating the aforementioned alkali solution.

These saponified surfaces are bonded with a polyvinyl alcohol-based compound.

In this way, a rear polarizing plate (BHB-1) was produced.

<Liquid Crystal Display Element and Liquid Crystal Display Device>

(TN mode liquid crystal display device)

In a 20-inch TN-mode liquid crystal display device (TH-20TA3, manufactured by Matsushita Electric Co.), the polarizing plate on the viewing side was replaced with the viewing-side polarizing plate (SHB-1) of the present invention, which was attached to the viewing side with an acrylic adhesive. The side is adhered in such a way that the optically anisotropic layer is on the side of the liquid crystal cell. And on the backlight side, a backlight-side polarizing plate (BHB-1) was adhered with an adhesive in such a manner that the optically anisotropic layer was on the liquid crystal cell side, thereby completing a display element. The transmission axis of the polarizer on the viewing side and the transmission axis of the polarizer on the backlight side are mounted to form an O-mode.

<Image Display Performance of Liquid Crystal Display Device>

The image display performance of the aforementioned liquid crystal display device was evaluated according to the following items. The results are shown in Table 38.

Observation side polarizers SHB-R1-SHB-R3 were also prepared in the same manner as explained above, except that AF-1 in the observation side polarizer (SHB-1) was replaced with AFR-1, AFR-2 and AFR-3 respectively , and a liquid crystal element and a liquid crystal display device were also obtained in the corresponding same manner. They were evaluated in the same manner as in Example E-1 as comparative examples.

(display image unevenness)

Using a measuring instrument (EZ-contrast 160D, manufactured by ELDIM Ltd.), visually observe the image display unevenness of the black display (L1):

A: There is no inhomogeneity at all (none of the 10 discriminators recognize it);

B: slightly non-uniform (identified by 1-5 out of 10 discriminators);

C: Unevenness is strongly generated (identified by 6 or more out of 10 discriminators).

(reflection of external light)

Using fluorescence, the reflection of external light was evaluated by visual observation at the following four levels:

AA: Changes in reflection but no disturbance at all;

A: The reflection changes but there is almost no interference;

B: Changes in reflection interfere but are permissible;

C: Interference of changes in reflection.

(shades of black display)

Using a measuring instrument (EZ-contrast 160D, manufactured by ELDIM Ltd.), the color tone change of the black display (L1) was observed with the naked eye:

AA: Not recognized at all (none of the 10 discriminators);

A: Slightly recognizable (1-2 out of 10 discriminators recognize);

B: Slightly recognizable (3-5 out of 10 discriminators recognize);

C: Can be strongly recognized (recognized by 6 or more out of 10 discriminators).

(brightness improvement performance)

The luminance in the front direction (cd/cm ² ) was measured with a luminance meter (BM-7, manufactured by Topcon Co.). As a comparative sample, the luminance without the luminance-improving film in the examples was also measured, and used to calculate the luminance improvement ratio, evaluated at the following levels:

A: Brightness improvement ratio is 1.5 or higher;

B: The luminance improvement ratio is 1.25 or more but less than 1.5;

C: The luminance improvement ratio is less than 1.25.

The uniformity of luminance was also evaluated by visually observing whether there was unevenness in the squint direction (45°).

(contrast and viewing angle)

A white display voltage of 2 V and a black display voltage of 6 V were applied to the liquid crystal cell of the liquid crystal display device, and the contrast ratio in the lateral direction (perpendicular to the rubbing direction of the cell) was investigated with a measuring instrument (EZ-contrast 160D, manufactured by ELDIM Ltd.) and viewing angles (the range of angles where the contrast ratio becomes 10 or higher):

AA: The change is not disruptive at all;

A: There are changes but little interference;

B: Change interference but allowable;

C: Change interference.

(hue change)

Use the same instrument as the evaluation of "contrast and viewing angle" to visually observe the level of hue change from the front to the viewing angle of 60° and evaluate according to the following criteria:

AA: The change is not disruptive at all;

A: There are changes but little interference;

B: Change interference but allowable;

C: Change interference.

The image quality of displayed images was evaluated for the display devices of Example E-1 and Comparative Examples E1-1 to E1-3 by the aforementioned method. The results are shown in Table 38.

Table 38 Observe side polarizer Image unevenness external light reflection shades of black Brightness Improvement Brightness unevenness contrast angle of view Hue change Example E-1 SHB-1 A A A A No A A A Comparative Example E1-1 SHB-R1 A C A A No B A A Comparative Example E1-2 SHB-R2 B B A A have B A BA Comparative Example E1-3 SHB-R3 B C B A have B B B

Example E-1 was satisfactory in all image display properties, and provided bright images with improved luminance without unevenness in luminance. Comparative Example E1-1 was poor in external light reflection and had insufficient contrast. Comparative Examples E1-2 and E1-3 were inferior in image unevenness, external light reflection, contrast and color tone change. Furthermore, unevenness in luminance occurs to result in insufficient uniformity of displayed images.

Therefore only the present invention can display bright and clear images.

Examples E-2-E-3

Observing side polarizers (SHB-2 and -3) were prepared in the same manner as in Example E-1, except that the low-refractive index layer (LL-1) in the antireflection film of the observation side polarizer (SHB-1) was used The lower index layer is replaced below. These polarizing plates (SHB-2 and -3) were then installed in a liquid crystal display device.

The characteristics of the polarizing plate and display device thus obtained were evaluated in the same manner as in Example E-1. The results are shown in Table 39.

<Low Refractive Index Layer>

(Low Refractive Index Layer AL-2)

Add 130 parts by weight of thermally crosslinkable fluoropolymer (JTA113, solid concentration: 6%, manufactured by JSR Corp.) with a refractive index of 1.42, 5 parts by weight of silica sol (MEK-ST, average particle diameter: 15nm, solid content: 30%, manufactured by Nissan Chemical Industries Ltd.), 15 parts by weight of hollow silica (CS60-IPA, average particle diameter: 60nm, shell thickness: 10nm, refractive index: 1.31, 20% by weight of iso Propanol dispersion (manufactured by Catalysts & Chemicals Ind.Co.), 6 parts by weight of the aforementioned sol liquid a, 50 parts by weight of methyl ethyl ketone and 60 parts by weight of cyclohexanone were mixed and passed through a pore diameter of 1 μm A polypropylene filter was used to obtain a coating liquid for a low refractive index layer. Using this coating solution under the same coating conditions as in Example E-1, a low refractive index layer (AL-2) was formed with a thickness of 100 nm, and an antireflection polarizing plate was prepared.

The obtained antireflection polarizing plate had a surface with a surface energy of 21 mN/m and a dynamic friction coefficient of 0.12.

(Low Refractive Index Layer AL-3)

Add 130 parts by weight of thermally crosslinkable fluoropolymer (JN-7228, solid concentration: 6%, manufactured by JSR Corp.) with a refractive index of 1.42, 3.5 parts by weight of DHPMA, 15 parts by weight of silica sol MEK -ST, 15 parts by weight of hollow silica CS60-IPA, 6 parts by weight of the aforementioned sol liquid a, 3 parts by weight of active polysiloxane X22-164C, 50 parts by weight of methyl ethyl ketone and 60 parts by weight and mixed with cyclohexanone, and filtered through a polypropylene filter with a pore size of 1 μm to obtain a coating solution for the low refractive index layer AL-3. Using this coating solution under the same coating conditions as in Example E-1, a low-refractive-index cured film having a thickness of 100 nm was formed, and an antireflection polarizing plate was prepared.

The obtained antireflection polarizing plate had a surface with a surface energy of 20 mN/m and a dynamic friction coefficient of 0.11.

(Antireflective Polarizer with Optical Compensation (Observation Side Polarizer/Top Polarizer))

Observation side polarizing plates (SHB2) and (SHB-3) were prepared in the same manner as in Example E-1 except that the antireflection polarizing plate in the observation side polarizing plate (SHB-1) was replaced with the aforementioned antireflection polarizing plate.

<OCB mode liquid crystal display device>

A polyimide film was provided as an alignment film on a glass substrate with ITO electrodes, and subjected to rubbing treatment. The two glass substrates thus obtained faced each other with rubbing directions parallel to each other and with a cell gap of 6 μm. A liquid crystal compound (ZLI1132, manufactured by Merck Inc.) having Δn of 0.1396 was poured into the cell gap to obtain a bend-aligned liquid crystal cell. On the prepared bend alignment unit in a laminated manner, the aforementioned polarizing plate (SHB-2 or SHB-3) was adhered to the viewing side of the unit with an adhesive in such a manner that the optical compensation sheet was on the liquid crystal unit side, and On the backlight side, a backlight side polarizing plate (BHB-1) was adhered with an adhesive in such a manner that the optically anisotropic layer was located on the liquid crystal cell side. The transmission axis of the polarizer on the viewing side and the transmission axis of the polarizer on the backlight side are mounted to form an O-mode.

Table 39 low refractive index layer Observe side polarizer Back polarizer Example E-2 AL-2 SHB-2 BHB-1 Example E-3 AL-3 SHB-3 BHB-1

The properties of Examples E-2 and E-3 were evaluated in the same manner as Example E-1. All show satisfactory results comparable to the performance of Example E-1.

[Example E-4]

<Preparation of anti-reflection film (AF-4)>

On a film Fujitac TD80UL (manufactured by Fuji Photo Film Co.), Pelnox C-4456-S7 (trade name of ATO-dispersed hard coat agent, solid: 45%, manufactured by Nippon Pelnox Ltd.) was coated and dried by ultraviolet irradiation hardened to form a conductive layer with a thickness of 1 μm. The film had a surface resistivity of about 10 ⁸ Ω/sq.

After the sample was left to stand under the condition of 25°C/65%RH for 1 hour, the surface resistivity was measured with a resistivity meter MCP-HT260 manufactured by Mitsubishi Chemical Corp.

(Coating solution for anti-glare hard coat)

50 parts by weight of a pentaerythritol triacrylate/pentaerythritol tetraacrylate mixture (Peta, manufactured by Nippon Kayaku Co.), 2 parts by weight of a curing initiator (Irgacure 184, manufactured by Ciba-Geigy Inc.), 5 parts by weight of propylene Acyl-styrene beads (manufactured by Soken Chemical and Engineering Co., particle diameter: 3.5 μm, refractive index: 1.55) as the first translucent particles, 5.2 parts by weight of styrene beads (manufactured by Soken Chemical and Engineering Co., particle diameter : 3.5 μm, refractive index: 1.60) as the second translucent particles, 10 parts by weight of the silane coupling agent KBM-5103 (manufactured by Shin-Etsu Chemical Co.) and 0.03 parts by weight of the following fluoropolymer (PF- 2) Mix with 50 parts by weight of toluene to obtain a coating liquid. The aforementioned cellulose acylate film having a conductive layer was unwound from a roll and coated with the coating solution to obtain a dry film thickness of 6.0 μm, and after the solvent evaporated, was cooled with a 160 W/cm air-cooled metal halide lamp (by Eyegraphics Co.) was irradiated with ultraviolet light at an irradiation intensity of 400 mW/cm ² and an irradiation amount of 300 mJ/cm ² to harden the coating, thereby obtaining an anti-glare hard coat layer.

Fluoropolymer (PF-3)

Mw: 4.5×10 ⁴ (calculated by molar composition ratio)

On this anti-glare layer, the coating liquid of the low-refractive-index layer (AL-1) was apply|coated with the gravure coater. After drying at 80°C, with an air-cooled metal halide lamp of 160 W/cm (manufactured by Eyegraphics Co.) in an atmosphere having an oxygen concentration of 1.0% by volume or less under nitrogen flushing at an irradiation intensity of 550 mW/cm and ^irradiating It was irradiated with ultraviolet light in an amount of 600 mJ/cm ² to obtain a low refractive index layer (refractive index: 1.43, film thickness: 86 nm). In this way, an antireflection film (AF-4) of the present invention was produced. The obtained antireflection film had an average reflectance of 2.3% and a haze of 43%.

Properties described in Example E-1 with respect to mechanical properties and durability were evaluated in the same manner as in Example E-1. The results were as satisfactory as the antireflection film of Example E-1.

<Preparation of anti-reflection polarizer with anti-glare performance>

A polarizing sheet is prepared by adsorbing iodine on a stretched polyvinyl alcohol film. The aforementioned film (AF-4) was subjected to a saponification process using an alkaline aqueous solution on its substrate side in a manner similar to that of Example E-1, and was adhered to one side of the polarizing sheet with a polyvinyl alcohol-based adhesive, which The adhesion was such that the transparent base film (cellulose acylate) of AF-4 was on the face of the polarizing sheet.

(Preparation of Optical Compensation Film)

(preparation of substrate)

(Preparation of Particle Dispersion (RL-2))

A particle dispersion composed of the following, a dispersant, and zirconia beads having a diameter of 0.3 mm were wet-dispersed in a bead mill to obtain a volume average particle diameter of 65 nm. The beads were separated from the obtained dispersion with a 200-mesh nylon cloth to obtain a particle dispersion (RL-2).

The particle size of the obtained particle dispersion was measured with a scanning electron microscope, and then the particle size distribution was measured with a scattering particle size distribution measuring apparatus LA920 (manufactured by Horiba Mfg. Co.). As a result, particles with a size of 300 nm or larger accounted for 0%.

^* Composition of particle dispersion (RL-2):

Hydrophobic silica (Aerosil R972, methyl-modified, primary particle size: 2.20 parts by weight

16nm, manufactured by Nippon Aerosil Co.)

Cellulose acetate propionate (degree of substitution: 2.70, acetate/propionate = 2.00 parts by weight

1/0.4)

Monolauryl phosphate (assistant dispersant) 0.22 parts by weight

Biphenyl diphenyl phosphate 0.08 parts by weight

Methyl acetate 71.0 parts by weight

Methanol 6.2 parts by weight

Acetone 6.1 parts by weight

Ethanol 6.1 parts by weight

1-butanol 6.1 parts by weight

The components of the following composition were heated and stirred in a mixing tank to obtain a cellulose acylate solution (A-2).

^* Composition of cellulose acylate solution (A-2):

Cellulose acetate propionate (degree of substitution: 2.70, acetate/propionate=1/0.4) 100 parts by weight

Triphenyl phosphate 7.5 parts by weight

The following plasticizer (logP1.88) 4.2 parts by weight

The following UV absorber: UV-E4 1.0 parts by weight

The following UV absorber: UV-E5 1.0 parts by weight

Methyl acetate 290 parts by weight

Methanol 25 parts by weight

Acetone 25 parts by weight

Ethanol 25 parts by weight

1-butanol 11 parts by weight

plasticizer

UV absorber

UV-E4: R ¹ =R ² ; -C ₅ H ₁₁ (t) UV-E5: R ¹ =R ² ; -C ₄ H ₉ (t)

(solution of delay modifier)

Pour into 16 parts by weight of the following retardation regulator, 74.4 parts by weight of methyl acetate, 6.4 parts by weight of methyl alcohol, 6.4 parts by weight of acetone, 6.4 parts by weight of ethanol and 6.4 parts by weight of isobutanol, heat and stir to obtain retardation Conditioner solution.

Latency modifier

In 475 parts by weight of cellulose acylate solution, add 36 parts by weight of retardation regulator solution and 14.8 parts by weight of inorganic particle dispersion (RL-2), then the mixture is fully stirred, and at room temperature (25° C.) After standing still for 3 hours, the obtained heterogeneous gel-like solution was cooled at -70°C for 6 hours, and stirred and heated at 50°C to obtain a completely dissolved coating dope.

The obtained coating dope was filtered and degassed in the same manner as in Example E-1, and cast with a drum casting apparatus.

The drum had a diameter of 200 mm and a width of 2000 mm with a hard chrome plated surface with an arithmetic mean roughness (Ra) of 0.010 μm and a ten point mean roughness (Rz) of 0.016 μm.

Casting was performed in the same manner as the tape casting described in Example E-1. After the surface temperature of the film on the drum reaches 40°C, the film is dried for 1 minute, then peeled off with a residual solvent amount of 50% by weight, passed through dry air at 140°C to make the residual solvent amount of the film 40% by weight, and then stretched. The film was stretched 17% in the transverse direction by the web frame and held at 130°C for 30 seconds at the stretched width. Thereafter, the film was dried with dry air at 130° C. for 20 minutes to obtain a rolled cellulose acylate film (CA-2) having a residual solvent content of 0.2% by weight, a thickness of 78 μm, a length of 1000 m and a width of 1.34 m. The rolled cellulose acylate film (CA-2) had a film thickness fluctuation of 2.8%, a curl value of 0.5/m, and the following surface irregularities:

Ra: 0.003 μm, Rz: 0.075 μm, Ry: 0.084 μm, Sm: 0.20 μm.

The obtained cellulose acylate film (CA-2) had a retardation value Re of 100 nm and a retardation value Rth of 50 nm at a wavelength of 590 nm.

(saponification process)

Cellulose acetate film (CA-2) passes under an induction heating roller at a temperature of 60°C, heats the surface of the film to 40°C, and then coats the alkali solution of the following composition with a coating amount of 12cc/ ^m2 by a rod coater (S-1), then left to stand for 15 seconds under a steam-type far-infrared heater (manufactured by Noritake Co.) heated at 110°C, and then coated with a coating amount of 3cc/ ^m2 by a similar rod coater Purify water. The film temperature in this operation was 40°C. Then rinse the film with water through a jet coater and squeeze out the water with an air knife for 3 times, and stand in a drying zone at 70°C for 5 seconds to dry.

^* Composition of alkaline solution (S-1)

Potassium hydroxide 8.55% by weight

Water 23.235% by weight

Isopropanol 54.20% by weight

Surfactant K-1: C ₁₄ H ₂₉ O(CH ₂ CH ₂ O) ₂₀ 1.0% by weight

Propylene Glycol 13.0% by weight

Defoamer Surfinol DF110D (formed by Nisshin Chemical 0.015% by weight

Industries manufacturing)

The saponified surface of the obtained film had a contact angle with water of 37° and a surface energy of 63 mN/m.

(Preparation of Oriented Film)

On the thus surface-treated film, the coating liquid of the oriented film of ^{the following} composition was coated with a coating amount of 28 mL/m by a bar coater, and dried by dry air at 60° C. for 60 seconds, and then passed through 90 C in dry air for 150 seconds.

Coating solution for oriented film:

The following denatured polyvinyl alcohol 20 parts by weight

Citric acid 0.05 parts by weight

Glutaraldehyde 0.5 parts by weight

Water 360 parts by weight

Methanol 120 parts by weight

denatured polyvinyl alcohol

(Rubbing of oriented film)

Rubbing treatment was performed on the surface of the oriented film by passing a rubbing roll on which a commercially available rubbing cloth was used in the longitudinal direction of the film and parallel to the conveying direction under an ambient condition of 25° C./45% RH.

(Formation of optically anisotropic layer)

On this oriented film, use #3.4 wire-wound bar to coat the trimethylolpropane triacrylate modified by 41.01 parts by weight of the discotic liquid crystal compound (DA) of the following structure and 4.06 parts by weight of ethylene oxide. ester (V#360, manufactured by Osaka Organic Chemical Industries, Ltd.), 0.90 parts by weight of cellulose acetate butyrate (CAB551-0.2, manufactured by Eastman Chemical Ltd.), 0.23 parts by weight of cellulose acetate butyrate (CAB531- 1, manufactured by Eastman Chemical Ltd.), 1.35 parts by weight of photopolymerization initiator (Irgacure907, manufactured by Ciba-Geigy Ltd.), 0.45 parts by weight of sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co.) and 0.40 A coating liquid in which parts by weight of a fluorinated surfactant (F-1) of the following structure was dissolved in 102 parts by weight of methyl ethyl ketone. The discotic liquid crystal compound was oriented by heating in a constant temperature zone at 130°C for 2 minutes, and then polymerized by ultraviolet irradiation for 1 minute in an atmosphere of 60°C with a high-pressure mercury lamp of 120 W/cm. Then cool by standing to room temperature. In this way, an optically anisotropic layer having a thickness of 2.0 µm was produced, whereby an optical compensation sheet (WV-1) was obtained.

Discotic liquid crystal compound (DA):

Fluorinated surfactant (F-1): C ₈ F ₁₇ CH ₂ CH ₂ O(CH ₂ CH ₂ O) ₁₀ H

(Antireflective Polarizer with Optical Compensation (Observation Side Polarizer))

(Observe the preparation of the side polarizer (SHB-4))

An optical compensation film (WV-1) having an optical compensation layer of a liquid crystal compound was subjected to a saponification process, and adhered to the opposite side with a polyvinyl alcohol-based adhesive such that the transparent base of WV-1 was positioned on the back of the antireflection film AF-4. The sheet side was polarized, thereby obtaining an observation-side polarizing plate (SHB-4).

(Preparation of back polarizer (BHB-2))

A polarizing sheet is prepared by adsorbing iodine on a stretched polyvinyl alcohol film. Triacetylcellulose film Fujitac TD80UL undergoes a saponification process and adheres to both sides of the polarizing sheet with a polyvinyl alcohol-based adhesive. On one side of the polarizing plate, a brightness improving film Vikuiti BEF-RP90/24 (manufactured by Sumitomo-3M Co.) was adhered with an acrylate adhesive, whereby a rear polarizing plate (BHB-2) was obtained.

<Liquid crystal display device>

In a 20-inch IPS mode liquid crystal device (W20-1c3000, manufactured by Hitachi Ltd.), the optical film provided therein was replaced with a polarizing plate (SHB-4), which was used in such a manner that the optical anisotropic layer was located on the liquid crystal cell side Acrylic adhesive adheres to viewing side. Also on the back side, a polarizing plate (BHB-2) was attached with an acrylic adhesive in such a manner that the protective film of the polarizing plate was on the liquid crystal cell side.

<Image Display Performance of Liquid Crystal Display Device>

The image quality of the image displayed on the display device of Example E-4 was evaluated in a similar manner to that of Example E-1. As a result satisfactory properties comparable to Example E-1 were obtained. Example E-5

<Anti-reflection film>

On the cellulose acylate film (CA-1) described in Example E-1, Peltron C-4456-S7 (ATO-trade name of dispersion hard coat agent, solid: 45%, manufactured by Nippon Pelnox Ltd. ), dried at 60°C for 150 seconds, and irradiated with ultraviolet light at an intensity of 400mW/ ^cm2 and an irradiation amount of 400mJ/ ^cm2 under nitrogen flushing with a 160W/cm air-cooled metal halide lamp (manufactured by Eyegraphics Co. Irradiated to obtain an antistatic layer with a thickness of 1 μm.

On the antistatic layer, a multilayer antireflection film (hard coat layer/medium refractive index layer/high refractive index layer) for the antireflection film of embodiment E-1 is formed with the same continuous coating as in embodiment E-1. layer/low refractive index layer) to obtain an antireflection film (AF-5).

<Optical Compensation Film>

(base)

The following components were poured into a mixing tank with stirring and stirred to obtain a cellulose acylate solution.

Cellulose triacetate with a substitution degree of 2.78 (6-position substitution 0.90) 89.3 parts by weight

Triphenyl phosphate (logP5.60) 7.6 parts by weight

The following plasticizer (logP2.54) 4.0 parts by weight

The following ultraviolet absorber: UV-1 1.0 parts by weight

The following UV absorber: UV-2 1.0 parts by weight

Particle dispersion (RL-2) (for solid) 0.15 parts by weight

Methyl acetate 290 parts by weight

Methanol 25 parts by weight

Acetone 25 parts by weight

Ethanol 25 parts by weight

1-butanol 25 parts by weight

Plasticizer:

(solution of delay modifier)

Pour into 17 parts by weight of the following retardation regulator, 74.4 parts by weight of methyl acetate, 6.4 parts by weight of methyl alcohol, 6.4 parts by weight of acetone, 6.4 parts by weight of ethanol and 6.4 parts by weight of isobutanol, heat and stir to obtain retardation Conditioner solution.

Latency modifier

In 464 parts by weight of cellulose acylate solution, add 36 parts by weight of retardation regulator solution, then the mixture is fully stirred, and left to stand at room temperature (25 ° C) for 3 hours, the obtained heterogeneous gel The solution was cooled at -70°C for 6 hours and heated with stirring at 50°C to obtain a completely dissolved coating dope.

The obtained coating dope was filtered and air bubbles were removed in the same manner as in Example E-1, whereby a coating dope was obtained.

Cast the coating dope by the tape casting method in Example E-1 to obtain a residual solvent amount of 0.25% by weight, a roll-shaped cellulose acylate film (CA- 3).

This cellulose acylate film (CA-3) had a retardation value Re of 51 nm and a retardation value Rth of 94 nm at a wavelength of 590 nm.

(Preparation of Optical Compensation Film)

As in Example E-4, an optical compensation film (WV-2) was prepared by forming an optically anisotropic layer on a substrate (CA-3).

<Preparation of anti-reflection polarizer with optical compensation function (observation side polarizer) (SHB-5)>

The base surface of the antireflection film (AF-5) and the base surface of the optical compensation film (WV-2) having an optically anisotropic layer of a liquid crystal compound were subjected to a saponification process. Using a polyvinyl alcohol-based adhesive, one side of the polarizing sheet used in Example E-1 was adhered to the base of AF-5, and the other side was adhered to the base of WV-2, thereby obtaining the observation Side polarizer (SHB-5).

<Preparation of Back Polarizer (BHB-3)>

Prepare back polarizing plate (BHB-3) in the same manner as embodiment E-1, just the optical compensation film of the back polarizing plate (BHB-1) in embodiment E-1 is replaced with optical compensation film (WV-2) .

<Liquid crystal display device>

In a 22-inch VA-mode liquid crystal display device (TH22-LH10, manufactured by Matsushita Electric Co.), the polarizing plate on the viewing side was replaced with the aforementioned polarizing plate (SHB-5) with an optically anisotropic layer on the liquid crystal cell side. way attached to the viewing side with an acrylic adhesive.

The properties of the polarizing plate and display device thus obtained were evaluated in the same manner as in Example E-1. The results were satisfactory as in Example E-1.

The invention has been described in detail and with reference to specific embodiments, but it will be apparent to those skilled in the art that various modifications and changes can be added within the scope and spirit of the invention.

This application is based on Japanese patent applications JP2003-434142, JP- 2004-6062, JP2004-35077, JP2004-65991 and JP2004-96227, the contents of which are incorporated herein by reference.

Claims (58)

1. An antireflection film, comprising: a transparent support; and A low-refractive-index layer having a refractive index lower than that of a transparent support, wherein the low-refractive-index layer is the outermost layer of an antireflection film, and the low-refractive-index layer comprises: hollow silica particles and lowering the antireflection film The surface free energy of the compound. 2. The antireflection film of claim 1, wherein the compound is at least one selected from the group consisting of polysiloxane compounds, fluorine-containing compounds, and fluoroalkylpolysiloxane compounds. 3. The antireflection film of claim 2, wherein the compound is a polysiloxane compound. 4. The antireflection film according to any of claims 1 to 3, wherein the low-refractive index layer includes a binder, and the compound includes a group reactive with the binder. 5. The antireflection film as claimed in any one of claims 1 to 4, wherein said compound comprises a (meth)acryloyl group. 6. An antireflection film, comprising: a transparent support; and A low-refractive-index layer having a refractive index lower than that of a transparent support, wherein the low-refractive-index layer is the outermost layer of an antireflection film, and the low-refractive-index layer comprises: hollow silicon dioxide particles and the ability to reduce antireflection The surface free energy of the thin film is the binder. 7. The antireflection film of claim 6, wherein the binder includes at least one of polysiloxane and fluorine. 8. The antireflection film according to claim 6 or 7, wherein the binder is a fluoropolymer. 9. The antireflection film according to any one of claims 6 to 8, wherein the binder is a compound having a (meth)acryloyl group. 10. The antireflection film as claimed in any one of claims 6-9, wherein said binder is a compound represented by formula (1): Wherein L represents a linking group with 1-10 carbon atoms; X represents a hydrogen atom or a methyl group; A represents a repeating unit derived from a vinyl monomer; x, y and z each represent the mol% of each repeating unit, and 30≤x≤60, 5≤y≤70 and 0≤z≤65 are satisfied. 11. The antireflection film according to any one of claims 1-10, wherein at least one of polysiloxane and fluoroalkyl group is segregated on the outer surface of the low refractive index layer, so that the photoelectron spectrum on the outer surface The spectral intensity in is at least 5 times greater than Si/C or F/C than Si/C or F/C at a depth from the outer surface of 80% of the thickness of the low index layer. 12. The antireflection film as claimed in any one of claims 1-11, wherein the surface free energy thereof is at most 25 mN/m. 13. The antireflection film according to any one of claims 1-12, comprising a layer containing at least one of a hydrolyzate of an organosilane and a partial condensate of an organosilane, wherein the hydrolyzate and the partial condensate are prepared in the presence of at least one of an acid catalyst and a metal chelate, and the organosilane is represented by formula (A): (R ¹⁰ ) _m Si(X) _4-m wherein R ¹⁰ represents a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; X represents a hydroxyl group or a hydrolyzable group; and m represents an integer of 1-3. 14. An antireflective film comprising: a transparent support; and a low-refractive-index layer having a refractive index lower than that of the transparent support, in The low refractive index layer has a refractive index of 1.30-1.55, The low refractive index layer is formed by: coating a curable composition on the transparent support; drying the curable composition; and passing ionizing radiation and applying at least one of heat to cure the curable composition, and The curable composition includes: (A) a curable substance including crosslinking or polymerizing functional groups; (B) hollow inorganic particles, the average particle size of which is 30%-150% of the thickness of the low refractive index layer, and the hollow inorganic particles have a refractive index of 1.17-1.40; (C) at least one of a first polymerization initiator capable of generating free radicals by ionizing radiation and a second polymerization initiator capable of generating free radicals by application of heat; and (D) capable of dissolving or Solvent for dispersing components (A)-(C). 15. The antireflection film according to claim 14, wherein said low-refractive index layer further comprises at least one selected from the group consisting of polysiloxane compounds, fluorine-containing compounds, and fluoroalkyl polysilicon compounds. Oxygen compounds. 16. The antireflection film according to claim 14 or 15, wherein the curable substance is a polyfunctional (meth)acrylate monomer. 17. The antireflection film according to any of claims 14-16, wherein said curable composition mainly contains a curable substance, which is a fluoropolymer, Wherein the fluoropolymer comprises: 35-85% by weight of fluorine atoms; and cross-linking or polymerizing functional groups, and The fluoropolymer is a copolymer, wherein the copolymer comprises: a first polymerizable unit of a fluorine-containing vinyl monomer; and a second polymerizable unit having a side branch comprising (meth)acryloyl and glycidol The functional group of one of the groups, and the copolymer has a main chain composed of carbon atoms. 18. The antireflection film according to any one of claims 14-17, wherein the curable composition further comprises at least one of an organosilane compound, a hydrolyzate of an organosilane compound, and a partial condensate of an organosilane compound, The organosilane compound is represented by formula (A1): (R ¹⁰¹ ) _m Si(X) _4-m wherein R ¹⁰¹ represents an alkyl group; X represents a hydroxyl group or a hydrolyzable group; and m represents an integer of 1-3. 19. An antireflective film comprising: a support comprising a cellulose acylate film having a thickness of 30 to 120 μm; An antireflection layer comprising in turn: at least one of a light-diffusing layer and a high-refractive-index layer, the high-refractive-index layer having a higher refractive index than the support; and having a higher refractive index than the support A low-refractive-index layer with a low refractive index, in The cellulose acylate film is a long film with a length of 100-5,000m and a width of at least 0.7m; the cellulose acylate film has a thickness fluctuation range of -3-3%; has a curling of -7-+7/m in the width direction, and The low refractive index layer includes hollow silica particles with a refractive index of 1.17-1.40. 20. The antireflection film as claimed in claim 19, wherein said cellulose acylate film satisfies the formulas (I) and (II): (I) 2.3≤SA'+SB'≤3.0, (II) 0≤SA'≤3.0 wherein SA' refers to the degree of substitution of an acetyl group that replaces a hydrogen atom of a hydroxyl group in cellulose; and SB' refers to the degree of substitution of an acyl group having 3 to 22 carbon atoms that replaces a hydrogen atom of a hydroxyl group in cellulose atom. 21. The antireflection film as claimed in claim 19 or 20, wherein said cellulose acylate film comprises polyhydric alcohol ester of aliphatic polyhydric alcohol and monocarboxylic acid as a plasticizer, and The cellulose acylate film has a moisture permeability of 20-260 g/m ² for 24 hours under the conditions of 25° C. and 90% RH. 22. The antireflection film of claim 21, wherein the monocarboxylic acid in the polyol ester includes at least one of an aromatic ring and an alicyclic ring. 23. The antireflection film as claimed in any of claims 19-22, wherein said cellulose acylate film has a bleed-out degree of 0-2.0%. 24. The antireflection film as claimed in any of claims 19-23, wherein said cellulose acylate film comprises a combination of an ultraviolet absorbing monomer having a molar extinction coefficient of at least 4,000 at 380 nm and an ethylenically unsaturated monomer. An ultraviolet absorbing copolymer, and the ultraviolet absorbing copolymer has a weight average molecular weight of 2,000-20,000. 25. The antireflection film according to any of claims 19-24, wherein said cellulose acylate film has a surface having a surface roughness measured according to the JIS B0601-1994 method: the arithmetic mean roughness (Ra) is 0.0005-0.1 μm; the ten-point average roughness (Rz) is 0.001-0.3 μm; and the average distance (Sm) of surface roughness is 2 μm at most, and The number of optical defects each having a visible size of at least 100 μm on the surface is at most 1/m 2 . 26. The antireflection film according to any of claims 19-25, wherein the reflected light from said antireflection film is on the respective planes of L ^* , a ^* and b ^* values in the color space CE1976L ^* a ^* b ^* The maximum variation within is 20%, Wherein the reflected light is regular reflected light of incident light with an incident angle of 5 degrees, the incident light has a wavelength of 380nm-780nm, and the incident light is light from CIE standard light source D65. 27. The antireflection film as claimed in any of claims 19-26, wherein the variation of the average reflectance in the wavelength range of 380nm-680nm before and after the weathering test is at most 0.4%, and The hue change ΔE of reflected light on the L ^* a ^* b chromaticity diagram is 15 at maximum. 28. The antireflection film according to any one of claims 19-27, wherein said low refractive index layer further comprises a composition comprising at least one of a hydrolyzate of an organosilane and a partial condensate of an organosilane One, and the organosilane is represented by formula (A2): R _m Si(X) _n Wherein X represents -OH, a halogen atom, -OR ¹⁰² or -OCOR ¹⁰² ; R and R ¹⁰² each represent a substituted or unsubstituted alkyl group with 1-10 carbon atoms; m+n=4, and m and n are each Represents an integer of 0 or greater. 29. A method for preparing an antireflection film, comprising: applying the curable composition to a transparent support; drying the curable composition; and Curing the curable composition by at least one of ionizing radiation and applying heat in an atmosphere having an oxygen concentration of not higher than 15% by volume, thereby forming a low-refractive index layer having a refractive index of 1.30-1.55 on a transparent support , in The curable composition includes: (A) a curable substance including crosslinking or polymerizing functional groups; (B) hollow inorganic particles, the average particle size of which is 30%-150% of the thickness of the low refractive index layer, and the hollow inorganic particles have a refractive index of 1.17-1.40; (C) at least one of a first polymerization initiator capable of generating free radicals by ionizing radiation and a second polymerization initiator capable of generating free radicals by application of heat; and (D) capable of dissolving or Solvent for dispersing components (A)-(C). 30. A polarizing plate comprising the antireflection film according to any one of claims 1-28. 31. A polarizer comprising polarizing sheets; and A transparent protective film on one side of the polarizer, the transparent protective film comprising the antireflection film of any one of claims 1-28. 32. A polarizer comprising: polarizing sheets; and a transparent protective film on each side of the polarizing sheet, in The transparent protective film on one side of the polarizer comprises a multilayer antireflection film, The multilayer antireflection film comprises a high-refractive-index layer whose refractive index is higher than that of the transparent protective film; and a low-refractive-index layer whose refractive index is lower than the refractive index of the transparent protective film, The high-refractive-index layer and the low-refractive-index layer are formed by sequentially applying their respective coating liquids, The low refractive index layer includes hollow inorganic particles having a refractive index of 1.17-1.37 and an average particle diameter of 30%-100% of the thickness of the low refractive index layer. 33. The polarizer according to claim 32, having a first light transmittance of 0.001%-0.3% at 700 nm under crossed Nicols conditions, and having a first light transmittance of 0.001 at 410 nm under crossed Nicols conditions. %-0.3% second transmittance. 34. The polarizer according to claim 32 or 33, wherein the reflected light from the polarizer has a maximum in-plane variation of L ^* , a ^* and b ^* values in the color space CE1976L ^* a ^* b ^* of 20%, Wherein the reflected light is regular reflected light of incident light with an incident angle of 5 degrees, the incident light has a wavelength of 380nm-780nm, and the incident light is light from CIE standard light source D65. 35. The polarizing plate according to any one of claims 32-34, wherein the light transmittance change and the polarization change of the polarizing plate before and after standing in an environment of 60° C. and 90% RH for 500 hours are in absolute values Each maximum is 3%. 36. The polarizing plate according to any one of claims 32-35, wherein the dimensional change of the polarizing plate in each direction of the absorption axis and the polarization axis before and after standing under the heating condition of 70° C. for 120 hours is within ± Within 0.6%. 37. The polarizing plate according to any one of claims 32-36, wherein an angle between a stretching axis of said transparent protective film and a stretching axis of said polarizing sheet is from 10° to less than 90°. 38. The polarizing plate as claimed in any one of claims 31 to 37, wherein the transparent protective film on the other side of said polarizing plate has an optical compensation film including an optically anisotropic layer. 39. The polarizing plate as claimed in claim 38, which has said polarizing sheet in turn; said transparent protective film on the other side of the polarizing sheet; and said optical compensation film, in The optically anisotropic layer includes a compound having a discotic structure, The disk-shaped surface of the disk-shaped structure is inclined relative to the film surface of the transparent protective film, and The angle between the disc surface and the film surface varies in the depth direction of the optically anisotropic layer. 40. A method for preparing a polarizer according to any one of claims 30-39, comprising: Feed polymer films for polarizing sheets; clamping each side of the polymer film; and The polymer film is stretched by applying tension to the polymer film while moving the gripper in the axial direction of the polymer film, in Stretching is carried out under the condition of satisfying formula (III): |L2-L1|＞0.4W Where L1 represents the trajectory of the first clamp from the real clamping start point to the real clamping release point on one side of the polymer film; L2 represents the trajectory of the second clamp from the real clamping start point to the real clamping release point on the other side of the polymer film point locus; and W represents the distance between the two real clamping release points of the first clamp and the second clamp, and The difference in moving speed between the first gripper and the second gripper is less than 1%. 41. The method of manufacturing a polarizing plate as claimed in claim 40, wherein the stretching is performed under the condition of maintaining the volatile matter content of the polymer film at least 5% by volume, and the volatile matter content is reduced while the polymer film shrinks. 42. The method for producing a polarizing plate as claimed in claim 40 or 41, which comprises sticking a transparent protective film on one side of said polarizing plate, and the protective film has an antireflection film. 43. An image display device comprising the antireflection film according to any one of claims 1-28 or the polarizing plate according to any one of claims 30-39. 44. The image display device according to claim 43, which is a liquid crystal display device. 45. The image display device according to claim 43, which is a transmissive, reflective or semi-transmissive liquid crystal display device in any mode of TN, STN, IPS, VA or OCB. 46. A liquid crystal display element, which sequentially comprises: upper polarizer; A liquid crystal cell comprising two cell substrates; and A lower polarizer, wherein the upper polarizer and the lower polarizer each sequentially include: an upper transparent protective film, a polarizing sheet, and a lower transparent protective film, and the lower polarizer includes a brightness improving film, in The upper transparent protective film includes: a transparent support and an anti-reflection film, the anti-reflective film includes a low-refractive-index layer with a refractive index lower than that of the transparent support, wherein the low-refractive-index layer is the uppermost layer of the upper transparent protective film. The outer layer, and the low refractive index layer include hollow inorganic particles having a refractive index of 1.17-1.37 and an average particle diameter of 30%-100% of the thickness of the low refractive index layer. 47. The liquid crystal display element as claimed in claim 46, wherein said low refractive index layer is a cured film formed by applying and curing a curable composition, Wherein the curable composition comprises: hollow inorganic particles, a fluoropolymer including curable reactive groups, and at least one of a hydrolyzate of an organosilane and a partial condensate of an organosilane, wherein the hydrolyzate and the partial condensation The compound is prepared in the presence of at least one of an acid catalyst and a metal chelate, and the organosilane is represented by formula (A): (R ¹⁰ ) _m Si(X) _4-m wherein R ¹⁰ represents a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; X represents a hydroxyl group or a hydrolyzable group; and m represents an integer of 1-3. 48. The liquid crystal display element according to claim 46 or 47, wherein said anti-reflection film comprises a layer between said low-refractive index layer and said transparent support having a refractive index higher than that of the transparent support. Refractive layer. 49. The liquid crystal display element according to claim 46 or 47, wherein said antireflection film includes an antireflection film having a refractive index higher than that of the transparent support between said low refractive index layer and said transparent support. Glare layer. 50. The liquid crystal display element according to any one of claims 46-49, wherein from the outermost side of the upper polarizing plate, the upper polarizing plate comprises in sequence: an anti-reflection film; a transparent support; a polarizing sheet; and another transparent Supports, which are bonded and integrated as upper polarizers. 51. The liquid crystal display element according to any one of claims 46-50, wherein the upper polarizing plate further comprises an optical compensation film on the side adjacent to the liquid crystal cell. 52. The liquid crystal display element according to any one of claims 46-51, wherein the lower polarizing plate comprises in order from the side adjacent to the liquid crystal cell: an optical compensation film; a polarizing film, a transparent protective film and a brightness improving film. 53. The liquid crystal display element as claimed in any one of claims 46-52, wherein said transparent support is a cellulose acylate film containing cellulose acylate, octanol- A plasticizer having a water partition coefficient (log P) of 0-10 and fine particles having an average primary particle diameter of 3-100 nm, and the cellulose acylate film has a thickness of 20-120 μm: (I) 2.3≤SA'+SB'≤3.0, (II) 0≤SA'≤3.0 wherein SA' refers to the degree of substitution of an acetyl group used to replace a hydrogen atom of a hydroxyl group in cellulose; and SB' refers to the degree of substitution of an acyl group having 3 to 22 carbon atoms used to replace a hydrogen atom of a hydroxyl group in cellulose . 54. The liquid crystal display element as claimed in any one of claims 46-53, wherein the reflected light from said antireflection film is on the respective planes of L ^* , a ^* and b ^* values in the color space CE1976L ^* a ^* b ^* within a variation of less than 15%, Wherein the reflected light is regular reflected light of incident light with an incident angle of 5 degrees, the incident light has a wavelength of 380nm-780nm, and the incident light is light from CIE standard light source D65. 55. The liquid crystal display element as claimed in any one of claims 46-53, wherein the variation of the average reflectance of the anti-reflection film in the wavelength range of 380nm-680nm before and after the weathering test is at most 0.5%, and The hue change ΔE of the reflected light from the antireflection film was 15 at the maximum on the L ^* a ^* b chromaticity diagram. 56. A liquid crystal display device comprising the liquid crystal display element according to any one of claims 46-55. 57. The liquid crystal display device of claim 56, further comprising a backlight. 58. The liquid crystal display device according to claim 56 or 57, which is a transmissive, reflective or semi-transmissive liquid crystal display device in any mode of TN, STN, IPS, VA or OCB.

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